feat(projman): add RFC system for feature tracking

Implement wiki-based Request for Comments system for capturing,
reviewing, and tracking feature ideas through their lifecycle.

New commands:
- /rfc-create: Create RFC from conversation or clarified spec
- /rfc-list: List RFCs grouped by status
- /rfc-review: Submit Draft RFC for review
- /rfc-approve: Approve RFC for sprint planning
- /rfc-reject: Reject RFC with documented reason

RFC lifecycle: Draft → Review → Approved → Implementing → Implemented

Integration:
- /sprint-plan detects approved RFCs and offers selection
- /sprint-close updates RFC status on completion
- clarity-assist suggests /rfc-create for feature ideas

New MCP tool: allocate_rfc_number

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

plugins/projman/commands/sprint-close.md

@@ -10,6 +10,7 @@ agent: orchestrator
 - skills/mcp-tools-reference.md
 - skills/lessons-learned.md
 - skills/wiki-conventions.md
+- skills/rfc-workflow.md
 - skills/progress-tracking.md
 - skills/git-workflow.md
 
@@ -31,11 +32,42 @@ Execute the sprint close workflow:
 4. **Save to Gitea Wiki** - Use `create_lesson` with metadata and implementation link
 5. **Update Wiki Implementation Page** - Change status to Implemented/Partial/Failed
 6. **Update Wiki Proposal Page** - Update overall status if all implementations complete
-7. **New Command Verification** - Remind user new commands require session restart
-8. **Update CHANGELOG** (MANDATORY) - Add changes to `[Unreleased]` section
-9. **Version Check** - Run `/suggest-version` to recommend version bump
-10. **Git Operations** - Commit, merge, tag, clean up branches
-11. **Close Milestone** - Update milestone state to closed
+7. **Update RFC Status (if applicable)** - See RFC Update section below
+8. **New Command Verification** - Remind user new commands require session restart
+9. **Update CHANGELOG** (MANDATORY) - Add changes to `[Unreleased]` section
+10. **Version Check** - Run `/suggest-version` to recommend version bump
+11. **Git Operations** - Commit, merge, tag, clean up branches
+12. **Close Milestone** - Update milestone state to closed
+
+## RFC Status Update (Step 7)
+
+If the sprint was linked to an RFC:
+
+1. **Check Sprint Completion Status:**
+   - All issues completed → RFC status = Implemented
+   - Partial completion → RFC status stays Implementing (note progress)
+   - Blocked/Failed → RFC status reverts to Draft (with notes)
+
+2. **Update RFC Page (if Implemented):**
+   - Change status: Implementing → Implemented
+   - Add Completion section with date and release version
+   - Link to lessons learned page
+   ```python
+   update_wiki_page(
+       page_name="RFC-NNNN:-Title",
+       content="[content with Implemented status and completion details]",
+       repo="org/repo"
+   )
+   ```
+
+3. **Update RFC-Index:**
+   - Remove from "## Implementing" section
+   - Add to "## Implemented" section with completion date and release
+
+4. **Handle Partial Completion:**
+   - Keep RFC in Implementing status
+   - Add progress notes to Implementation section
+   - Next sprint can continue the work
 
 **Don't skip lessons learned!** Future sprints will benefit from captured insights.