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>

plugins/projman/skills/branch-security.md

@@ -0,0 +1,98 @@
+---
+name: branch-security
+description: Branch detection, protection rules, and branch-aware authorization
+---
+
+# Branch Security
+
+## Purpose
+
+Defines branch detection, classification, and branch-aware authorization rules.
+
+## When to Use
+
+- **Planner agent**: Before planning any sprint work
+- **Orchestrator agent**: Before executing any sprint tasks
+- **Executor agent**: Before modifying any files
+- **Commands**: `/sprint-plan`, `/sprint-start`, `/sprint-close`
+
+---
+
+## Branch Detection
+
+```bash
+git branch --show-current
+```
+
+## Branch Classification
+
+| Branch Pattern | Classification | Capabilities |
+|----------------|----------------|--------------|
+| `development`, `develop`, `feat/*`, `fix/*`, `dev/*` | Development | Full access |
+| `staging`, `stage/*` | Staging | Read-only code, can create issues |
+| `main`, `master`, `prod/*` | Production | READ-ONLY, no changes |
+
+---
+
+## Behavior by Classification
+
+### Development Branches
+- Full planning and execution capabilities
+- Can create/modify issues, wiki, lessons
+- Can execute tasks and modify code
+- Normal operation
+
+### Staging Branches
+- Can create issues to document bugs
+- CANNOT modify application code
+- Can modify `.env` files only
+- Warn user about limitations
+
+### Production Branches
+- READ-ONLY mode enforced
+- Cannot create issues or modify anything
+- MUST stop immediately and instruct user to switch
+
+---
+
+## Stop Messages
+
+### Production Branch
+```
+BRANCH SECURITY: Production branch detected
+
+You are on branch: [branch-name]
+Planning and execution are NOT allowed on production branches.
+
+Please switch to a development branch:
+  git checkout development
+
+Or create a feature branch:
+  git checkout -b feat/[issue-number]-[description]
+```
+
+### Staging Branch Warning
+```
+STAGING BRANCH: Limited capabilities
+
+Available: Create issues to document bugs
+Not available: Sprint planning, code modifications
+
+Switch to development for full capabilities:
+  git checkout development
+```
+
+---
+
+## Branch Naming Conventions
+
+| Type | Pattern | Example |
+|------|---------|---------|
+| Features | `feat/<issue>-<desc>` | `feat/45-jwt-service` |
+| Bug fixes | `fix/<issue>-<desc>` | `fix/46-login-timeout` |
+| Debugging | `debug/<issue>-<desc>` | `debug/47-memory-leak` |
+
+**Validation:**
+- Issue number MUST be present
+- Prefix MUST be `feat/`, `fix/`, or `debug/`
+- Description: kebab-case (lowercase, hyphens)