refactor(projman): extract skills and consolidate commands

Major refactoring of projman plugin architecture:

Skills Extraction (17 new files):
- Extracted reusable knowledge from commands and agents into skills/
- branch-security, dependency-management, git-workflow, input-detection
- issue-conventions, lessons-learned, mcp-tools-reference, planning-workflow
- progress-tracking, repo-validation, review-checklist, runaway-detection
- setup-workflows, sprint-approval, task-sizing, test-standards, wiki-conventions

Command Consolidation (17 → 12 commands):
- /setup: consolidates initial-setup, project-init, project-sync (--full/--quick/--sync)
- /debug: consolidates debug-report, debug-review (report/review modes)
- /test: consolidates test-check, test-gen (run/gen modes)
- /sprint-status: absorbs sprint-diagram via --diagram flag

Architecture Cleanup:
- Remove plugin-level mcp-servers/ symlinks (6 plugins)
- Remove plugin README.md files (12 files, ~2000 lines)
- Update all documentation to reflect new command structure
- Fix documentation drift in CONFIGURATION.md, COMMANDS-CHEATSHEET.md

Commands are now thin dispatchers (~20-50 lines) that reference skills.
Agents reference skills for domain knowledge instead of inline content.

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

docs/UPDATING.md

@@ -162,7 +162,7 @@ If that doesn't work:
    ls ~/.claude/plugins/marketplaces/leo-claude-mktplace/mcp-servers/gitea/.venv
    ls ~/.claude/plugins/marketplaces/leo-claude-mktplace/mcp-servers/netbox/.venv
    ```
-3. If missing, the symlinks won't resolve. Run setup.sh as shown above.
+3. If missing, run setup.sh as shown above.
 4. Restart Claude Code session
 5. Check logs for specific errors