docs: update CHANGELOG with complete version history and add maintenance rules

CHANGELOG.md updates:
- Added proper dates to all versions (2.1.0, 2.0.0, 1.0.0, 0.1.0)
- Added v2.0.0 section (was missing)
- Added v1.0.0 section with initial features
- Updated v2.2.0 with version consolidation changes
- Follows Keep a Changelog format

CLAUDE.md updates:
- Added "Changelog Maintenance (MANDATORY)" section
- Documented required steps when releasing new version
- Added Semantic Versioning reference
- Clarified version display rules

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

CHANGELOG.md

@@ -15,18 +15,26 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 - `metadata` wrapper for description/version in marketplace.json
 - Keywords to all plugin manifests for better discoverability
 - `commands` and `agents` directory references to plugin manifests
+- Versioning rule: version displayed only in main README.md title
 
 ### Changed
 - Updated marketplace.json with required fields per Claude Code spec
 - Fixed installation documentation to use official Claude Code methods
 - Prioritized public HTTPS URL over Tailscale SSH URL in documentation
 - Updated all plugin manifests with author, homepage, repository, license fields
+- Consolidated version display to main README.md title only
+- Removed version numbers from plugin documentation titles
 
 ### Fixed
 - Plugin manifests now include all required fields per Claude Code spec
 - Installation section uses `extraKnownMarketplaces` instead of undocumented `pluginMarketplace`
 
-## [2.1.0] - Previous Release
+### Removed
+- `docs/references/` directory (obsolete planning documents)
+- Version numbers from individual plugin README titles
+- Version section from plugins/projman/README.md
+
+## [2.1.0] - 2026-01-15
 
 ### Added
 - `docs/CANONICAL-PATHS.md` - Single source of truth for all file paths
@@ -37,16 +45,12 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 - Update documentation (`docs/UPDATING.md`)
 - `/initial-setup` slash command
 - File creation governance rules in CLAUDE.md
-- Architecture diagram specifications in `docs/architecture/`
 - `.scratch/` directory for transient work
 - `scripts/` directory for setup automation
-- `docs/architecture/` for Draw.io diagrams
-- `docs/workflows/` for workflow documentation
 
 ### Changed
 - Replaced `docs/CORRECT-ARCHITECTURE.md` reference with `docs/CANONICAL-PATHS.md`
 - Added mandatory path verification section to CLAUDE.md
-- Reorganized documentation into `docs/references/`, `docs/architecture/`, `docs/workflows/`
 - Updated CLAUDE.md with file creation governance
 
 ### Fixed
@@ -54,21 +58,44 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
 ### Removed
 - Organization/workspace GID variable (no longer needed)
-- Deprecated `cmdb-assistant/` plugin
 - Development output files (test scripts, status reports)
 - IDE-specific workspace files
 - Stray files from project root
 
-## [0.1.0] - Initial Release
+## [2.0.0] - 2026-01-06
 
 ### Added
-- projman plugin for sprint management
+- Full Gitea integration with wiki, milestones, dependencies
+- Parallel execution batching via dependency graph
+- Wiki tools for lessons learned (`create_lesson`, `search_lessons`)
+- Milestone tools (`list_milestones`, `create_milestone`, `update_milestone`)
+- Dependency tools (`list_issue_dependencies`, `create_issue_dependency`, `get_execution_order`)
+- Validation tools (`validate_repo_org`, `get_branch_protection`)
+- MCP servers bundled inside plugins (not shared at root)
+
+### Changed
+- MCP server architecture: bundled in plugins instead of shared at root
+- Configuration uses `${CLAUDE_PLUGIN_ROOT}/mcp-servers/` paths
+
+## [1.0.0] - 2025-12-15
+
+### Added
+- projman plugin with basic sprint commands
+- `/sprint-plan`, `/sprint-start`, `/sprint-status`, `/sprint-close` commands
+- `/labels-sync` command for label taxonomy synchronization
+- Three-agent model (planner, orchestrator, executor)
+- Gitea MCP server with issue and label tools
+- 43-label taxonomy system
+- Hybrid configuration system (system + project level)
+- Branch-aware security model
+
+## [0.1.0] - 2025-12-01
+
+### Added
+- Initial repository structure
+- projman plugin structure (planned)
 - projman-pmo plugin structure (planned)
 - project-hygiene plugin for cleanup automation
-- Gitea MCP server
-- Wiki.js MCP server
-- 43-label taxonomy system
-- Lessons learned capture system
-- Hybrid configuration system (system + project level)
-- Three-agent model (planner, orchestrator, executor)
-- Branch-aware security model
+- claude-config-maintainer plugin structure
+- cmdb-assistant plugin structure
+- Basic marketplace manifest