feat: add unified code quality dashboard with multiple validators

- Add validator_type field to scans and violations (architecture,
  security, performance)
- Create security validator with SEC-xxx rules
- Create performance validator with PERF-xxx rules
- Add base validator class for shared functionality
- Add validate_all.py script to run all validators
- Update code quality service with validator type filtering
- Add validator type tabs to dashboard UI
- Add validator type filter to violations list
- Update stats response with per-validator breakdown
- Add security and performance rules documentation
- Add chat-bubble icons to icon library

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

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

mkdocs.yml

@@ -40,6 +40,7 @@ nav:
     - Authentication & RBAC: architecture/auth-rbac.md
     - Frontend Structure: architecture/frontend-structure.md
     - Models Structure: architecture/models-structure.md
+    - Background Tasks: architecture/background-tasks.md
     - API Consolidation:
       - Proposal: architecture/api-consolidation-proposal.md
       - Migration Status: architecture/api-migration-status.md
@@ -117,6 +118,8 @@ nav:
     - Contributing Guide: development/contributing.md
     - Code Quality: development/code-quality.md
     - Architecture Rules: development/architecture-rules.md
+    - Security Rules: development/security-rules.md
+    - Performance Rules: development/performance-rules.md
     - Code Quality Dashboard: development/code-quality-dashboard-implementation.md
     - Icons Guide: development/icons-guide.md
     - Naming Conventions: development/naming-conventions.md