refactor(db): migrate interview preparation

Move durable user-owned interview preparation into an additive provider-aware migration. Preserve questions, answers, practice state, ordering, and application cascade semantics.

JobTrackerApi.Tests/MigrationChainTests.cs

@@ -117,6 +117,7 @@ public sealed class MigrationChainTests
         Assert.Contains("CREATE TABLE IF NOT EXISTS `CvVariantVersions`", script, StringComparison.Ordinal);
         Assert.Contains("CREATE TABLE IF NOT EXISTS `ApplicationChecklistItems`", script, StringComparison.Ordinal);
         Assert.Contains("CREATE TABLE IF NOT EXISTS `CoverLetterVersions`", script, StringComparison.Ordinal);
+        Assert.Contains("CREATE TABLE IF NOT EXISTS `InterviewPrepItems`", script, StringComparison.Ordinal);
         Assert.Contains("`UiLanguage` varchar(16)", script, StringComparison.Ordinal);
         Assert.All(
             Regex.Matches(script, "CONSTRAINT `([^`]+)`").Select(match => match.Groups[1].Value),
@@ -820,6 +821,63 @@ public sealed class MigrationChainTests
         Assert.Empty(await db.Database.GetPendingMigrationsAsync());
     }
 
+    [Fact]
+    public async Task Interview_prep_item_adoption_preserves_user_content_and_practice_state()
+    {
+        await using var connection = new SqliteConnection("Data Source=:memory:");
+        await connection.OpenAsync();
+        await using var db = Context(connection);
+        var migrator = db.GetService<IMigrator>();
+        await migrator.MigrateAsync("20260830131000_AdoptCoverLetterVersionSchema");
+        await ExecuteAsync(connection, """
+            INSERT INTO Companies (Name) VALUES ('Fixture company');
+            INSERT INTO JobApplications
+                (CompanyId, JobTitle, DateApplied, SavedAt, Status, ResponseReceived, OwnerUserId,
+                 HasResume, HasCoverLetter, HasPortfolio, HasOtherAttachment, IsDeleted)
+            VALUES
+                (1, 'Fixture role', '2026-08-01T09:00:00', '2026-07-20T09:00:00',
+                 'Applied', 0, 'owner-fixture', 0, 0, 0, 0, 0);
+            CREATE TABLE "InterviewPrepItems" (
+                "Id" INTEGER NOT NULL CONSTRAINT "PK_InterviewPrepItems" PRIMARY KEY AUTOINCREMENT,
+                "OwnerUserId" TEXT NOT NULL, "JobApplicationId" INTEGER NOT NULL,
+                "Category" TEXT NOT NULL, "Title" TEXT NOT NULL, "Content" TEXT NULL,
+                "Source" TEXT NOT NULL, "IsPrepared" INTEGER NOT NULL, "SortOrder" INTEGER NOT NULL,
+                "CreatedAtUtc" TEXT NOT NULL, "UpdatedAtUtc" TEXT NOT NULL,
+                CONSTRAINT "FK_InterviewPrepItems_JobApplications_JobApplicationId"
+                    FOREIGN KEY ("JobApplicationId") REFERENCES "JobApplications" ("Id") ON DELETE CASCADE
+            );
+            INSERT INTO "InterviewPrepItems"
+                ("OwnerUserId", "JobApplicationId", "Category", "Title", "Content", "Source",
+                 "IsPrepared", "SortOrder", "CreatedAtUtc", "UpdatedAtUtc")
+            VALUES
+                ('owner-fixture', 1, 'star', 'Describe a difficult incident',
+                 'Situation, task, action, result', 'user', 1, 10,
+                 '2026-08-30T09:00:00+00:00', '2026-08-30T09:10:00+00:00'),
+                ('owner-fixture', 1, 'technical', 'Explain dependency injection',
+                 'Accepted suggestion, then edited', 'ai', 0, 20,
+                 '2026-08-30T09:00:00+00:00', '2026-08-30T09:15:00+00:00');
+            """);
+
+        await migrator.MigrateAsync();
+        Assert.Equal("Situation, task, action, result", await ScalarAsync<string>(connection,
+            "SELECT Content FROM InterviewPrepItems WHERE SortOrder = 10;"));
+        Assert.Equal(1L, await ScalarAsync<long>(connection,
+            "SELECT IsPrepared FROM InterviewPrepItems WHERE SortOrder = 10;"));
+
+        await migrator.MigrateAsync("20260830131000_AdoptCoverLetterVersionSchema");
+        Assert.Equal("ai", await ScalarAsync<string>(connection,
+            "SELECT Source FROM InterviewPrepItems WHERE SortOrder = 20;"));
+        await migrator.MigrateAsync();
+        Assert.Equal(1L, await ScalarAsync<long>(connection, """
+            SELECT COUNT(*) FROM sqlite_master
+            WHERE type = 'index' AND name = 'IX_InterviewPrepItems_Owner_Job_Sort';
+            """));
+
+        await ExecuteAsync(connection, "DELETE FROM JobApplications WHERE Id = 1;");
+        Assert.Equal(0L, await ScalarAsync<long>(connection, "SELECT COUNT(*) FROM InterviewPrepItems;"));
+        Assert.Empty(await db.Database.GetPendingMigrationsAsync());
+    }
+
     private static JobTrackerContext Context(SqliteConnection connection)
     {
         var currentUser = new Mock<ICurrentUserService>();

JobTrackerApi/Migrations/20260830132000_AdoptInterviewPrepItemSchema.cs

@@ -0,0 +1,70 @@
+using System;
+using JobTrackerApi.Data;
+using Microsoft.EntityFrameworkCore.Infrastructure;
+using Microsoft.EntityFrameworkCore.Migrations;
+
+#nullable disable
+
+namespace JobTrackerApi.Migrations;
+
+/// <summary>
+/// Moves durable user-owned interview preparation into migration ownership without replacing
+/// questions, answers, research, or practice state.
+/// </summary>
+[DbContext(typeof(JobTrackerContext))]
+[Migration("20260830132000_AdoptInterviewPrepItemSchema")]
+public sealed class AdoptInterviewPrepItemSchema : Migration
+{
+    protected override void Up(MigrationBuilder migrationBuilder)
+    {
+        if (ActiveProvider.Contains("MySql", StringComparison.OrdinalIgnoreCase))
+        {
+            migrationBuilder.Sql("""
+                CREATE TABLE IF NOT EXISTS `InterviewPrepItems` (
+                    `Id` int NOT NULL AUTO_INCREMENT,
+                    `OwnerUserId` varchar(255) NOT NULL,
+                    `JobApplicationId` int NOT NULL,
+                    `Category` varchar(32) NOT NULL,
+                    `Title` varchar(500) NOT NULL,
+                    `Content` longtext NULL,
+                    `Source` varchar(16) NOT NULL,
+                    `IsPrepared` tinyint(1) NOT NULL,
+                    `SortOrder` int NOT NULL,
+                    `CreatedAtUtc` datetime(6) NOT NULL,
+                    `UpdatedAtUtc` datetime(6) NOT NULL,
+                    PRIMARY KEY (`Id`),
+                    CONSTRAINT `FK_InterviewPrepItems_JobApplications_JobApplicationId`
+                        FOREIGN KEY (`JobApplicationId`) REFERENCES `JobApplications` (`Id`) ON DELETE CASCADE
+                ) CHARACTER SET=utf8mb4;
+                CREATE INDEX IF NOT EXISTS `IX_InterviewPrepItems_Owner_Job_Sort`
+                    ON `InterviewPrepItems` (`OwnerUserId`, `JobApplicationId`, `SortOrder`);
+                """);
+            return;
+        }
+
+        migrationBuilder.Sql("""
+            CREATE TABLE IF NOT EXISTS "InterviewPrepItems" (
+                "Id" INTEGER NOT NULL CONSTRAINT "PK_InterviewPrepItems" PRIMARY KEY AUTOINCREMENT,
+                "OwnerUserId" TEXT NOT NULL,
+                "JobApplicationId" INTEGER NOT NULL,
+                "Category" TEXT NOT NULL,
+                "Title" TEXT NOT NULL,
+                "Content" TEXT NULL,
+                "Source" TEXT NOT NULL,
+                "IsPrepared" INTEGER NOT NULL,
+                "SortOrder" INTEGER NOT NULL,
+                "CreatedAtUtc" TEXT NOT NULL,
+                "UpdatedAtUtc" TEXT NOT NULL,
+                CONSTRAINT "FK_InterviewPrepItems_JobApplications_JobApplicationId"
+                    FOREIGN KEY ("JobApplicationId") REFERENCES "JobApplications" ("Id") ON DELETE CASCADE
+            );
+            CREATE INDEX IF NOT EXISTS "IX_InterviewPrepItems_Owner_Job_Sort"
+                ON "InterviewPrepItems" ("OwnerUserId", "JobApplicationId", "SortOrder");
+            """);
+    }
+
+    protected override void Down(MigrationBuilder migrationBuilder)
+    {
+        // Preserve durable user-authored preparation from pre-migration installations.
+    }
+}

JobTrackerApi/Models/InterviewPrepItem.cs

@@ -8,8 +8,7 @@ namespace JobTrackerApi.Models;
 // own questions — and nothing regenerates it.
 //
 // One table for every category rather than a table per category: they differ only by label, and a new
-// category must not need a migration. Reconciler-owned
+// category must not need a migration. Migration-owned through an additive provider-aware adoption.
-// (docs/infrastructure/database-ownership.md); its migration is a no-op.
 public sealed class InterviewPrepItem
 {
     public int Id { get; set; }

JobTrackerApi/Services/StartupInitializationExtensions.cs

@@ -712,32 +712,9 @@ public static class StartupInitializationExtensions
                     EnsureColumn(c, "AiInteractions", "EstimatedTokenCount", "ALTER TABLE AiInteractions ADD COLUMN EstimatedTokenCount INTEGER NOT NULL DEFAULT 0;");
                 }
 
-                // Phase 5.5: user-owned interview preparation (not the AI cache InterviewPrepNote).
-                static void EnsureInterviewPrepItemsTable(DbConnection c)
-                {
-                    Exec(c, """
-        CREATE TABLE IF NOT EXISTS "InterviewPrepItems" (
-            "Id" INTEGER NOT NULL CONSTRAINT "PK_InterviewPrepItems" PRIMARY KEY AUTOINCREMENT,
-            "OwnerUserId" TEXT NOT NULL,
-            "JobApplicationId" INTEGER NOT NULL,
-            "Category" TEXT NOT NULL,
-            "Title" TEXT NOT NULL,
-            "Content" TEXT NULL,
-            "Source" TEXT NOT NULL,
-            "IsPrepared" INTEGER NOT NULL,
-            "SortOrder" INTEGER NOT NULL,
-            "CreatedAtUtc" TEXT NOT NULL,
-            "UpdatedAtUtc" TEXT NOT NULL,
-            CONSTRAINT "FK_InterviewPrepItems_JobApplications_JobApplicationId" FOREIGN KEY ("JobApplicationId") REFERENCES "JobApplications" ("Id") ON DELETE CASCADE
-        );
-        """);
-                    Exec(c, """CREATE INDEX IF NOT EXISTS "IX_InterviewPrepItems_Owner_Job_Sort" ON "InterviewPrepItems" ("OwnerUserId", "JobApplicationId", "SortOrder");""");
-                }
-
                 ReconcileGmailConnectionColumns(conn);
                 EnsureCareerProfileTables(conn);
                 ReconcileAiInteractionUsageColumns(conn);
-                EnsureInterviewPrepItemsTable(conn);
 
                 // Once the base app tables exist, provision this reconciler-owned schema set and
                 // stamp its historical migration before later migrations rebuild JobApplications.
@@ -1131,27 +1108,6 @@ public static class StartupInitializationExtensions
                     DropMalformedMySqlTable(conn, "CoverLetterVersions", "CreatedAtUtc", "datetime");
                     DropMalformedMySqlTable(conn, "InterviewPrepItems", "CreatedAtUtc", "datetime");
 
-                    if (!HasMySqlTable(conn, "InterviewPrepItems") && HasMySqlTable(conn, "JobApplications"))
-                    {
-                        using var cmd = conn.CreateCommand();
-                        cmd.CommandText = @"CREATE TABLE IF NOT EXISTS `InterviewPrepItems` (
-        `Id` int NOT NULL AUTO_INCREMENT,
-        `OwnerUserId` varchar(255) NOT NULL,
-        `JobApplicationId` int NOT NULL,
-        `Category` varchar(32) NOT NULL,
-        `Title` varchar(500) NOT NULL,
-        `Content` longtext NULL,
-        `Source` varchar(16) NOT NULL,
-        `IsPrepared` tinyint(1) NOT NULL,
-        `SortOrder` int NOT NULL,
-        `CreatedAtUtc` datetime(6) NOT NULL,
-        `UpdatedAtUtc` datetime(6) NOT NULL,
-        PRIMARY KEY (`Id`),
-        CONSTRAINT `FK_InterviewPrepItems_JobApplications_JobApplicationId` FOREIGN KEY (`JobApplicationId`) REFERENCES `JobApplications` (`Id`) ON DELETE CASCADE
-        );";
-                        cmd.ExecuteNonQuery();
-                    }
-
                     EnsureMySqlAutoIncrementPrimaryKey(conn, "InterviewPrepItems", "Id");
                     EnsureMySqlIndex(conn, "InterviewPrepItems", "IX_InterviewPrepItems_Owner_Job_Sort", "`OwnerUserId`, `JobApplicationId`, `SortOrder`");
 

JobTrackerApi/Services/StartupSchemaOwnership.cs

@@ -29,6 +29,7 @@ internal static class StartupSchemaOwnership
         "GmailReviewDecisions",
         "ImapConnections",
         "InterviewPrepNotes",
+        "InterviewPrepItems",
         "JobApplications",
         "JobEvents",
         "Jobs",
@@ -61,7 +62,6 @@ internal static class StartupSchemaOwnership
         "CareerProfileVersions",
         "CareerProjects",
         "CareerSkills",
-        "InterviewPrepItems",
     };
 
     // Historical migrations contain guarded compatibility bootstraps for these tables so direct

docs/audits/audit-remediation-backlog.md

@@ -558,7 +558,7 @@ SEC-008 implements the same durable state machine with `<final>.uploading` and `
 
 ### P3-1 — Reduce dual schema ownership incrementally
 
-**Status (2026-08-30): in progress.** All 49 model tables now have an executable, disjoint creation-owner classification. Nineteen formerly reconciler-created tables—including authentication support, email-provider connections, CV persistence/history, job-workspace AI notes, append-only AI interactions, workflow checklists, and cover-letter history—have moved through additive provider-aware migrations with legacy-row preservation, downgrade/retry safety, startup-DDL removal, fresh SQLite runtime proof and generated MariaDB SQL. The Gmail decision migration also closes its missing MariaDB creation path. Sixteen startup-created tables remain; see `docs/verification/jt-019-schema-ownership.md` and V-194–V-205.
+**Status (2026-08-30): in progress.** All 49 model tables now have an executable, disjoint creation-owner classification. Twenty formerly reconciler-created tables—including authentication support, email-provider connections, CV persistence/history, job-workspace AI notes, append-only AI interactions, workflow checklists, cover-letter history, and durable interview preparation—have moved through additive provider-aware migrations with legacy-row preservation, downgrade/retry safety, startup-DDL removal, fresh SQLite runtime proof and generated MariaDB SQL. The Gmail decision migration also closes its missing MariaDB creation path. Fifteen startup-created tables remain; see `docs/verification/jt-019-schema-ownership.md` and V-194–V-206.
 
 - **Findings/scope:** JT-019; inventory reconciler operations and move stable schema ownership to EF migrations in small steps.
 - **Dependencies:** provider upgrade fixtures and P2-2 restore safety.

docs/audits/verification-log.md

@@ -237,3 +237,4 @@ Output was reduced to filenames and commit counts. The token artifact appears un
 | V-203 | Ownership/migration chain; populated adoption/downgrade/retry; usage/FK/index assertions; MariaDB script; full backend | Repository root / disposable local SQLite | Move append-only AI interaction history to explicit migration ownership without losing generated results or usage data | PASS — focused ownership/migration 15/15; result JSON, mode, provider and usage counters survive adoption, downgrade and re-upgrade; both indexes exist; deleting the parent application cascades through history; generated MariaDB SQL is provider-safe; startup no longer creates the table; full backend 731/731 | MariaDB SQL generated only; no provider account or production migration. Historical compatibility bootstrap and guarded counter/shape/index repairs remain. Eighteen reconciler-owned tables remain | JT-019 AI interaction transfer complete; checklist/document/preparation tables continue incrementally |
 | V-204 | Ownership/migration chain; populated adoption/downgrade/retry; workflow/FK/index assertions; MariaDB script; full backend | Repository root / disposable local SQLite | Move application workflow checklist state to migration ownership without losing automatic or manual progress | PASS — focused ownership/migration 16/16; auto-completed system and pending manual items survive adoption, downgrade and re-upgrade; idempotency/order indexes exist; deleting the parent application cascades through checklist items; generated MariaDB SQL is provider-safe; startup no longer creates the table; full backend 732/732 | MariaDB SQL generated only; no provider account or production migration. Guarded malformed-empty/index/auto-increment repair remains temporarily. Seventeen reconciler-owned tables remain | JT-019 checklist transfer complete; cover-letter and interview-preparation tables continue incrementally |
 | V-205 | Ownership/migration chain; populated adoption/downgrade/retry; document/FK/index assertions; MariaDB script; full backend | Repository root / disposable local SQLite | Move append-only cover-letter revision history to migration ownership without losing recoverable documents | PASS — focused ownership/migration 17/17; manual and AI revisions plus source/action metadata survive adoption, downgrade and re-upgrade; owner/job/version index exists; deleting the parent application cascades through history; generated MariaDB SQL is provider-safe; startup no longer creates the table; full backend 733/733 | MariaDB SQL generated only; no provider account or production migration. Guarded malformed-empty/index/auto-increment repair remains temporarily. Sixteen reconciler-owned tables remain | JT-019 cover-letter history transfer complete; interview-preparation items and career-profile aggregate continue incrementally |
+| V-206 | Ownership/migration chain; populated adoption/downgrade/retry; practice-state/FK/index assertions; MariaDB script; full backend | Repository root / disposable local SQLite | Move durable interview-preparation items to migration ownership without losing user or AI preparation content | PASS — focused ownership/migration 18/18; user-authored and AI-generated questions, answers, prepared state and source metadata survive adoption, downgrade and re-upgrade; owner/job/sort index exists; deleting the parent application cascades through preparation items; generated MariaDB SQL is provider-safe; startup no longer creates the table; full backend 734/734 | MariaDB SQL generated only; no provider account or production migration. Guarded malformed-empty/index/auto-increment repair remains temporarily. Fifteen reconciler-owned tables remain | JT-019 feature-table transfers complete; the Career Profile aggregate and Identity group remain dependency-aware batches |

docs/infrastructure/database-ownership.md

@@ -70,7 +70,7 @@ Created by EF migrations, never by the reconciler:
 `ApplicationChecklistItems`, `Attachments`, `Companies`, `CoverLetterVersions`,
 `Correspondences`, `CvExtractionRuns`, `CvUploadArtifacts`, `CvVariants`, `CvVariantVersions`,
 `EmailDrafts`, `EmailSendAttempts`, `GmailConnections`,
-`GmailReviewDecisions`, `ImapConnections`, `InterviewPrepNotes`, `JobApplications`, `JobEvents`, `Jobs`,
+`GmailReviewDecisions`, `ImapConnections`, `InterviewPrepItems`, `InterviewPrepNotes`, `JobApplications`, `JobEvents`, `Jobs`,
 `MicrosoftGraphConnections`, `RuleSettings`, `SystemEmailSettings`, `TailoredCvDrafts`,
 `TrustedDevices`, `TwoFactorRecoveryCodes`, `UserNotifications`, `UserOperations`, `UserRuleSettings`,
 and `UserSessions`.
@@ -123,6 +123,10 @@ manual tasks; application deletion remains cascading.
 revisions retain their source/action metadata and owner/job/version ordering; application deletion
 remains cascading.
 
+`InterviewPrepItems` moved in `20260830132000_AdoptInterviewPrepItemSchema`. User-authored and
+AI-generated questions, answers, preparation state, sources, and ordering are retained; application
+deletion remains cascading.
+
 The reconciler may **repair** these (add a missing column, add an index, fix a non-`AUTO_INCREMENT`
 primary key) and may seed the default `RuleSettings` row — but it must never `CREATE TABLE` them.
 It used to create `RuleSettings`, which is precisely why a clean install failed with
@@ -133,8 +137,7 @@ It used to create `RuleSettings`, which is precisely why a clean install failed
 Created by `StartupInitializationExtensions`, with a **no-op migration** holding the model snapshot:
 
 `CareerProfiles`, `CareerProfileVersions`, the six CareerProfile children (`CareerExperiences`,
-`CareerEducations`, `CareerSkills`, `CareerProjects`, `CareerCertifications`, `CareerLanguages`),
+`CareerEducations`, `CareerSkills`, `CareerProjects`, `CareerCertifications`, `CareerLanguages`).
-`InterviewPrepItems`.
 
 The seven ASP.NET Identity tables are also currently reconciler-owned, despite older wording that
 called them migration-owned: `AspNetRoles`, `AspNetUsers`, `AspNetRoleClaims`, `AspNetUserClaims`,
@@ -156,7 +159,7 @@ No-op migrations, each with a comment explaining why:
 | `20260719085904_AddApplicationChecklistItems` | historical no-op; ownership transferred by `20260830130000_AdoptApplicationChecklistSchema` |
 | `20260719094728_SyncCareerChildKeyLengths` | snapshot sync only |
 | `20260719120954_AddCoverLetterVersions` | historical no-op; ownership transferred by `20260830131000_AdoptCoverLetterVersionSchema` |
-| `20260719145044_AddInterviewPrepItems` | `InterviewPrepItems` |
+| `20260719145044_AddInterviewPrepItems` | historical no-op; ownership transferred by `20260830132000_AdoptInterviewPrepItemSchema` |
 
 ### Dependency guards
 

docs/verification/jt-019-schema-ownership.md

@@ -39,6 +39,8 @@ cohesive table groups. It does not attempt to delete the legacy reconciler whole
   stable system keys, manual steps, completion state, and user ordering.
 - Added `20260830131000_AdoptCoverLetterVersionSchema` for append-only document history, retaining
   manual and AI-approved text plus source/action metadata.
+- Added `20260830132000_AdoptInterviewPrepItemSchema` for durable interview-practice content,
+  retaining user and AI questions, answers, prepared state, source metadata, and ordering.
 - Corrected the ownership runbook: new tables now default to migrations; the reconciler is legacy
   compatibility code to retire one dependency group at a time.
 
@@ -76,14 +78,17 @@ migration.
   re-upgrade; deleting the parent application still cascades through its workflow items.
 - Representative manual and AI cover-letter revisions survive adoption, downgrade, and re-upgrade;
   deleting the parent application still cascades through document history.
+- Representative user-authored and AI-generated interview-preparation items survive adoption,
+  downgrade, and re-upgrade with practice state intact; their ordering index and application cascade
+  remain effective.
 - Generated MariaDB SQL contains the provider-correct `SystemEmailSettings` DDL.
-- Full backend: 733/733 passed after the cover-letter history transfer.
+- Full backend: 734/734 passed after the interview-preparation transfer.
 - Fresh application startup over a new disposable SQLite database applied
   `20260830120000_AdoptSystemEmailSettingsSchema` and reached the healthy listening state.
 
 ## Remaining JT-019 work
 
-Sixteen model tables remain startup-created, including the Identity group and several tables
+Fifteen model tables remain startup-created: the Career Profile aggregate and Identity group.
 with parent dependencies. Transfer them in small dependency-aware migrations with blank, populated,
 retry and MariaDB runtime proof. Column/index repairs must remain until historical upgrade fixtures
 prove each one redundant.

docs/work-programmes/master-progress.md

@@ -55,6 +55,7 @@ Updated: 2026-08-30
 - Moved append-only AI interaction history into a provider-aware migration; generated results, modes, providers, usage counters, indexes, and application cascades are preserved.
 - Moved application checklist workflow state into a provider-aware migration; system-key idempotency, manual tasks, ordering, completion state, and application cascades are preserved.
 - Moved append-only cover-letter revision history into a provider-aware migration; manual and AI text, source/action metadata, ordering, and application cascades are preserved.
+- Moved durable interview-preparation items into a provider-aware migration; user and AI content, answers, practice state, sources, ordering, and application cascades are preserved.
 
 ### In progress
 
@@ -85,7 +86,7 @@ Updated: 2026-08-30
 - Focused frontend: 2 suites, 6 tests passed.
 - Full frontend: 64 suites, 272 tests passed.
 - Next production build and TypeScript: passed.
-- Full backend: 733/733 tests passed after the cover-letter history JT-019 transfer.
+- Full backend: 734/734 tests passed after the interview-preparation JT-019 transfer.
 - Portable Playwright launcher: resolved the user-local .NET 9 SDK; backend Release build passed with 0 warnings/errors.
 - Playwright: initial full run 9/10 exposed the intentional mobile Settings control change; updated focused rerun passed 1/1. A final complete browser rerun remains in the end-of-batch gate.
 - Focused backend match/intelligence verification: 34/34 passed.