docs: reorganize tree, restore architecture + research from archive, add Phase 0 reports

Active docs/ was stub scaffolding while the real docs sat in docs/_archive/.
Restore and correct them, and record the Phase 0 work.

- docs/architecture/current.md: verified system map (from archived SYSTEM_OVERVIEW,
  9 corrections against code).
- docs/research/competitors.md: sourced competitor analysis (from archived
  PRODUCT_RESEARCH, feature matrix corrected).
- docs/decisions/ADR-002-job-application-model.md: the Job/JobApplication split.
- docs/application-discovery-report.md, docs/implementation-roadmap.md,
  docs/phase-0-foundation-report.md, docs/career-workspace-branch-assessment.md.
- Remove 10 zero-byte placeholder files that advertised content that never existed.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

docs/CHANGELOG_AI_WORK.md

@@ -0,0 +1,212 @@
+# AI Development Changelog
+
+This document tracks work completed by AI coding assistants.
+
+Purpose:
+
+- Maintain project history.
+- Record architectural decisions.
+- Track incomplete work.
+- Prevent repeated investigations.
+- Help future AI sessions understand previous changes.
+
+---
+
+# How To Use
+
+After making meaningful changes, update this file.
+
+Include:
+
+- Date.
+- Task.
+- Summary.
+- Files changed.
+- Decisions.
+- Testing performed.
+- Remaining work.
+
+---
+
+# Current Status
+
+## Application State
+
+Status:
+
+Active development.
+
+The application is functional but undergoing major UX, architecture, and product improvements.
+
+---
+
+# Completed Work
+
+## Authentication
+
+Status:
+
+In progress.
+
+Completed:
+
+- Existing authentication reviewed.
+- OAuth architecture analysed.
+
+Remaining:
+
+- Full signup flow.
+- Google login.
+- Microsoft login.
+- Password reset improvements.
+- Two factor authentication.
+
+---
+
+## Career Workspace
+
+Status:
+
+Planning phase.
+
+Completed:
+
+- Product direction defined.
+- Architecture documented.
+- Competitor research completed.
+
+Remaining:
+
+- Master career profile.
+- CV builder redesign.
+- Theme system.
+- AI workflows.
+
+---
+
+## Job Workflow
+
+Status:
+
+Core product.
+
+Completed:
+
+- Existing job tracking functionality.
+
+Remaining:
+
+- Improved add-job workflow.
+- Better application pipeline.
+- Better onboarding.
+
+---
+
+# Current Development Session
+
+Date:
+
+YYYY-MM-DD
+
+## Objective
+
+Describe current goal.
+
+---
+
+## Work Completed
+
+Example:
+
+- Updated authentication pages.
+- Refactored settings layout.
+- Added validation.
+
+---
+
+## Files Changed
+
+Example:
+
+Backend:
+
+- path/file.cs
+
+Frontend:
+
+- path/file.tsx
+
+Documentation:
+
+- docs/file.md
+
+---
+
+## Testing
+
+Completed:
+
+- Build successful.
+- Tests passed.
+
+Not completed:
+
+- Manual testing required.
+- External service testing required.
+
+---
+
+# Architectural Decisions
+
+## Decision
+
+Date:
+
+Reason:
+
+Impact:
+
+---
+
+# Known Issues
+
+## Issue
+
+Description:
+
+Possible causes:
+
+Next investigation:
+
+---
+
+# Blocked Items
+
+## Item
+
+Reason blocked:
+
+Required input:
+
+---
+
+# Recommended Next Tasks
+
+Priority order:
+
+1.
+
+2.
+
+3.
+
+---
+
+# AI Notes
+
+Important context for future sessions:
+
+- Read MASTER_IMPLEMENTATION_GUIDE.md first.
+- Do not redesign without reviewing existing architecture.
+- Prefer incremental changes.
+- Ask before destructive decisions.