feat: Add project-planner skill, simplify planning architecture

Architecture:
- /plan command = all plan operations (create, review, sync, etc.)
- project-planner skill = lightweight detection, suggests /plan usage
- No duplication, clear separation of concerns

Changes:
- Add skills/project-planner/SKILL.md (detection + suggestions only)
- Remove ROADMAP.md references (single source: docs/PLAN.md)
- Update project-organizer detection logic

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

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

agents/project-organizer.md

@@ -586,10 +586,9 @@ Example: "Claude, [do something]"
 ## Project Planning
 
 This project uses `/plan` for task management:
-- `docs/ROADMAP.md` - Long-term vision and version roadmap
-- `docs/PLAN.md` - Current active tasks
+- `docs/PLAN.md` - Project goals, progress, and active tasks
 
-Run `/plan --sync` to update your plan from git commits.
+Run `/plan --review` to see current status or `/plan --sync` to update from git.
 
 ## Tips & Best Practices
 
@@ -605,7 +604,7 @@ Run `/plan --sync` to update your plan from git commits.
 **Detection Logic**:
 - Check for `.claude/` directory → Claude Code project
 - Check dependencies for `mcp`, `@modelcontextprotocol/sdk` → MCP server (use MCP template)
-- Check for `ROADMAP.md`, `PLAN.md` → Planning workflow active
+- Check for `docs/PLAN.md` → Planning workflow active
 - Otherwise → Use general Claude Code template
 
 Always suggest creating CLAUDE.md if .claude/ directory exists but CLAUDE.md doesn't

skills/project-planner/SKILL.md

@@ -0,0 +1,74 @@
+---
+name: project-planner
+description: Detects stale project plans and suggests /plan command usage. Triggers on: sync plan, update plan, check status, plan is stale, track progress, project planning.
+---
+
+# Project Planner Skill
+
+Lightweight awareness layer for `docs/PLAN.md`. Detects when plans need attention and points to `/plan` command.
+
+## Purpose
+
+This skill does NOT manage plans directly. It:
+- Detects when `docs/PLAN.md` exists or is missing
+- Identifies stale plans (no recent updates vs git activity)
+- Suggests appropriate `/plan` commands
+
+All plan operations go through the `/plan` command.
+
+## Detection Logic
+
+### Plan Missing
+```
+No docs/PLAN.md found
+→ Suggest: /plan "describe your project goal"
+```
+
+### Plan Stale
+```
+docs/PLAN.md last modified: 5 days ago
+git log shows: 12 commits since then
+→ Suggest: /plan --sync
+```
+
+### Uncommitted Work
+```
+git status shows: 5 modified files
+docs/PLAN.md "In Progress" section outdated
+→ Suggest: /plan --status
+```
+
+### Session Start
+```
+Resuming work on project with docs/PLAN.md
+→ Suggest: /plan --review
+```
+
+## Quick Reference
+
+| Situation | Suggestion |
+|-----------|------------|
+| No plan exists | `/plan "goal"` |
+| Plan is stale | `/plan --sync` |
+| Need to see plan | `/plan --review` |
+| Update progress | `/plan --status` |
+| Capture thinking | `/plan --capture` |
+| Start fresh | `/plan --clear "new goal"` |
+
+## Staleness Heuristics
+
+A plan is considered **stale** when:
+- Last modified > 3 days ago AND
+- Git shows commits since last modification AND
+- Commits relate to plan topics (feat:, fix:, refactor:)
+
+A plan **needs review** when:
+- Session just started
+- Significant uncommitted changes exist
+- User mentions progress or completion
+
+## Notes
+
+- This skill only suggests, never modifies
+- All operations delegate to `/plan` command
+- Single source of truth: `docs/PLAN.md`