test(S01/T01): Added a job-scoped Gmail matching contract with backend-…

- JobTrackerApi/Controllers/GmailController.cs
- JobTrackerApi/Services/GmailOAuthService.cs
- JobTrackerApi.Tests/GmailControllerTests.cs
- .gsd/milestones/M001/slices/S01/S01-PLAN.md
- .gsd/KNOWLEDGE.md

.gsd/milestones/M001/M001-ROADMAP.md

@@ -50,16 +50,16 @@ This milestone is complete only when all are true:
 
 ## Slices
 
-- [x] **S01: Smarter Gmail import and matching** `risk:high` `depends:[]`
+- [ ] **S01: Smarter Gmail import and matching** `risk:high` `depends:[]`
   > After this: User can connect Gmail, review likely messages or threads for a job, and import correspondence with much better matching confidence and less manual cleanup.
 
-- [x] **S02: Stronger AI application package drafting** `risk:high` `depends:[S01]`
+- [ ] **S02: Stronger AI application package drafting** `risk:high` `depends:[S01]`
   > After this: From an imported job plus profile/CV context, the app generates materially better tailored CV and cover-letter drafts that feel specific and usable.
 
-- [x] **S03: Reply and follow-up drafting from real thread context** `risk:medium` `depends:[S01,S02]`
+- [ ] **S03: Reply and follow-up drafting from real thread context** `risk:medium` `depends:[S01,S02]`
   > After this: Inside a job, the user can generate follow-up and reply drafts grounded in imported correspondence and saved application context, then edit them before sending manually.
 
-- [x] **S04: Daily control loop surfaces** `risk:medium` `depends:[S01,S03]`
+- [ ] **S04: Daily control loop surfaces** `risk:medium` `depends:[S01,S03]`
   > After this: The job table works as the primary overview and the follow-up/dashboard surfaces clearly show what needs attention next for an individual user.
 
 - [ ] **S05: End-to-end trust and workflow polish** `risk:low` `depends:[S01,S02,S03,S04]`