Add fork display, version selector, and admin cleanup features

Registry Features:
- Fork tracking with forked_from/forked_version metadata
- Forked tools show "Forked from" notice on detail page
- Original tools display "Forks" section listing all forks
- Fork count in tool stats
- API: GET /api/v1/tools/<owner>/<name>/forks

GUI Improvements:
- Version selector dropdown for registry installs
- Fetch available versions via GET /api/v1/tools/<owner>/<name>/versions
- "Latest" option plus all available versions listed

Admin Features:
- POST /api/v1/admin/cleanup/rejected endpoint
- Maintenance section in admin dashboard
- "Dry Run" and "Run Cleanup" buttons for rejected version cleanup
- Configurable grace period (default 7 days)

Documentation:
- Updated CHANGELOG.md with all recent changes

Co-Authored-By: Claude Opus 4.5 <[email protected]>

CHANGELOG.md

@@ -1 +1,53 @@
-# Auto-deploy test Tue 13 Jan 2026 03:09:44 AM AST
+# Changelog
+
+All notable changes to CmdForge will be documented in this file.
+
+## [Unreleased]
+
+### Added
+
+#### Registry Features
+- **Fork tracking and display**: Tools now track their fork origin with `forked_from` and `forked_version` metadata
+  - Forked tools show a "Forked from" notice on the tool detail page
+  - Original tools display a "Forks" section listing all forks
+  - Fork count displayed in tool stats
+  - API endpoint: `GET /api/v1/tools/<owner>/<name>/forks`
+
+- **Version selector for installs**: Users can select specific versions when installing tools from the registry
+  - Version dropdown in registry page populated via `GET /api/v1/tools/<owner>/<name>/versions`
+  - "Latest" option plus all available versions listed
+  - Selected version passed to install worker
+
+- **Auto-cleanup rejected versions**: Admin maintenance feature to purge rejected tool submissions
+  - API endpoint: `POST /api/v1/admin/cleanup/rejected`
+  - Parameters:
+    - `days` (default: 7) - grace period before deletion
+    - `dry_run` (default: false) - preview mode without actual deletion
+  - Admin dashboard UI with "Dry Run" and "Run Cleanup" buttons
+  - Shows count of rejected versions pending cleanup
+
+#### GUI Improvements
+- Version display and bump buttons in publish dialog
+- Auto-fetch registry version when opening publish dialog
+- Fork detection during publish workflow
+- Always refresh tools page after publish dialog closes
+
+#### Admin Features
+- Maintenance section in admin dashboard
+- Rejected version count display
+- Cleanup result modal with detailed output
+
+### Fixed
+- VERSION_EXISTS error showing after successful publish (made endpoint idempotent by checking config_hash)
+- My Tools page listing every version separately (now consolidated by tool name)
+- GUI not refreshing after publish dialog closes
+
+### Changed
+- Publish endpoint now returns success if same config_hash already exists (idempotent)
+- My Tools page groups versions by tool name, showing version count and list
+
+---
+
+## Previous Changes
+
+See git history for changes prior to this changelog.