chore(spec): complete hook-enhancement-v2 and move to completed

- All 5 phases implemented: SessionStart guidance, namespace markers,
  PostToolUse hook, PreCompact hook, testing
- 1319 tests passing, 86.20% code coverage
- RETROSPECTIVE.md generated with lessons learned
- Project moved from active/ to completed/

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: zircote

…2-19-hook-enhancement-v2/ARCHITECTURE.md …2-19-hook-enhancement-v2/ARCHITECTURE.mddocs/spec/active/2025-12-19-hook-enhancement-v2/ARCHITECTURE.md renamed to docs/spec/completed/2025-12-19-hook-enhancement-v2/ARCHITECTURE.md docs/spec/active/2025-12-19-hook-enhancement-v2/ARCHITECTURE.md renamed to docs/spec/completed/2025-12-19-hook-enhancement-v2/ARCHITECTURE.md

@@ -7,7 +7,8 @@ project_status: complete
 current_phase: 5
 implementation_started: 2025-12-19T00:00:00Z
 last_session: 2025-12-19T00:00:00Z
-last_updated: 2025-12-19T00:00:00Z
+last_updated: 2025-12-19T18:45:00Z
+completion_date: 2025-12-19
 ---
 
 # Hook Enhancement v2 - Implementation Progress
@@ -76,3 +77,9 @@ This document tracks implementation progress against the spec plan.
 - PROGRESS.md initialized from IMPLEMENTATION_PLAN.md
 - 22 tasks identified across 5 phases
 - Ready to begin implementation with Task 1.1
+
+### 2025-12-19 - Final Session
+- All 5 phases completed (17 done, 3 skipped)
+- 1319 tests passing, 86.20% coverage
+- RETROSPECTIVE.md created
+- Project moved to completed/