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/rfc-reject.md

@@ -0,0 +1,90 @@
+---
+description: Reject an RFC with documented reason, marking it as declined
+agent: planner
+---
+
+# Reject RFC
+
+## Skills Required
+
+- skills/mcp-tools-reference.md
+- skills/rfc-workflow.md
+- skills/rfc-templates.md
+
+## Purpose
+
+Transition an RFC to Rejected status with a documented reason. Rejected RFCs remain in the wiki for historical reference but are marked as declined.
+
+## Invocation
+
+Run `/rfc-reject <number>` where number is the RFC number:
+- `/rfc-reject 0006`
+- `/rfc-reject 6` (leading zeros optional)
+
+## Workflow
+
+1. **Validate RFC Number**
+   - Normalize input (add leading zeros if needed)
+   - Fetch RFC page: `RFC-NNNN: *`
+
+2. **Check Current Status**
+   - Parse frontmatter to get current status
+   - **STOP** if status is not "Draft" or "Review"
+   - Error: "RFC-NNNN is in [status] status. Only Draft or Review RFCs can be rejected."
+
+3. **Require Rejection Reason**
+   - Prompt: "Please provide the rejection reason (required):"
+   - **STOP** if no reason provided
+   - Error: "Rejection reason is required to document why this RFC was declined."
+
+4. **Update RFC Page**
+   - Change status: [current] → Rejected
+   - Update "Updated" date
+   - Add/update Decision section:
+     ```markdown
+     ## Decision
+
+     **Decision:** Rejected
+     **Date:** YYYY-MM-DD
+     **Decided By:** @[current user or maintainer]
+
+     **Reason:**
+
+     [User-provided rejection reason]
+     ```
+
+5. **Update RFC-Index**
+   - Remove entry from current section ("## Draft" or "## In Review")
+   - Add entry to "## Rejected" section with reason summary
+
+6. **Confirm Rejection**
+   - Display updated status
+   - Note that RFC remains in wiki for reference
+
+## Visual Output
+
+```
++----------------------------------------------------------------------+
+|  PROJMAN - RFC Rejection                                             |
++----------------------------------------------------------------------+
+
+RFC-0006: Proposed Feature has been rejected.
+
+Status: Review → Rejected
+Reason: Out of scope for current project direction
+
+The RFC remains in the wiki for historical reference.
+If circumstances change, a new RFC can be created.
+```
+
+## Validation Errors
+
+- **RFC not found**: "RFC-NNNN not found. Check the number with /rfc-list"
+- **Wrong status**: "RFC-NNNN is [status]. Only Draft or Review RFCs can be rejected."
+- **No reason provided**: "Rejection reason is required. Please document why this RFC is being declined."
+
+## Notes
+
+- Rejected is a terminal state
+- To reconsider, create a new RFC that references the rejected one
+- Rejection reasons help future contributors understand project direction