feat(create-plan): add iterative cross-model plan review and Cursor variant

Add a configurable reviewer phase to all create-plan variants (claude-code,
codex, opencode) that sends the plan to a second CLI/model for iterative
feedback (max 5 rounds). Supported reviewer CLIs: codex, claude, cursor.

Add new Cursor Agent CLI variant with full skill, templates, and
workspace-discovery-based prerequisites (.cursor/rules/).

Update README and docs/CREATE-PLAN.md with Cursor install/verify,
reviewer CLI requirements, and supported reviewer CLIs table.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

skills/create-plan/cursor/templates/continuation-runbook.md

@@ -0,0 +1,134 @@
+# Continuation Runbook: [Plan Title]
+
+## Reference Files (START HERE)
+
+Upon resumption, these files in this folder are the ONLY source of truth:
+
+| File | Purpose | When to Use |
+|------|---------|-------------|
+| `continuation-runbook.md` | Full context reproduction + execution workflow | Read FIRST |
+| `story-tracker.md` | Current progress and status | Check/update BEFORE and AFTER every story |
+| `milestone-plan.md` | Complete plan with specifications | Reference implementation details |
+| `original-plan.md` | Original approved plan | Reference original intent |
+| `final-transcript.md` | Final planning transcript | Reference reasoning/context |
+
+Do NOT reference planner-private files during implementation.
+
+## Skill Workflow Guardrails
+
+- Invoke relevant skills before action using workspace discovery (`.cursor/rules/`).
+- Announce which skill is being used and why.
+- If a checklist-driven skill applies, track checklist execution explicitly.
+
+---
+
+## Quick Resume Instructions
+
+1. Read this runbook completely.
+2. Check `story-tracker.md`.
+3. Find next `pending` story and mark as `in-dev` before starting.
+4. Implement the story.
+5. Update tracker immediately after each change.
+
+---
+
+## Mandatory Execution Workflow
+
+Work from this folder (`ai_plan/YYYY-MM-DD-<short-title>/`) and always follow this order:
+
+1. Read `continuation-runbook.md` first.
+2. Execute stories milestone by milestone.
+3. After completing a milestone:
+   - Run lint/typecheck/tests, prioritizing changed files for speed.
+   - Commit locally (**DO NOT PUSH**).
+   - Stop and ask user for feedback.
+4. If feedback is provided:
+   - Apply feedback changes.
+   - Re-run checks for changed files.
+   - Commit locally again.
+   - Ask for milestone approval.
+5. Only move to next milestone after explicit approval.
+6. After all milestones are completed and approved:
+   - Ask permission to push.
+   - If approved, push.
+   - Mark plan status as `completed`.
+
+---
+
+## Git Note
+
+`ai_plan/` is intentionally local and must stay gitignored. Do not treat inability to commit plan-file updates inside `ai_plan/` as an error.
+
+---
+
+## Full Context Reproduction
+
+### Project Overview
+[What this project/feature is about]
+
+### User Requirements
+[All gathered requirements]
+
+### Scope
+[In scope / out of scope]
+
+### Dependencies
+[External dependencies, prerequisites, related systems]
+
+---
+
+## Key Specifications
+
+### Type Definitions
+```typescript
+// Copy-paste ready type definitions
+```
+
+### Enums & Constants
+```typescript
+// All enums/constants needed
+```
+
+### API Endpoints
+```typescript
+// Request/response shapes
+```
+
+---
+
+## Critical Design Decisions
+
+| Decision | Chosen Approach | Alternatives Rejected | Rationale |
+|----------|-----------------|----------------------|-----------|
+| [Topic] | [What we chose] | [Other options] | [Why] |
+
+---
+
+## Verification Commands
+
+### Lint (changed files first)
+```bash
+# example: <lint-command> <changed-file-1> <changed-file-2>
+```
+
+### Typecheck
+```bash
+# example: <typecheck-command>
+```
+
+### Tests (target changed scope first)
+```bash
+# example: <test-command> <related spec/file>
+```
+
+---
+
+## File Quick Reference
+
+| File | Purpose |
+|------|---------|
+| `original-plan.md` | Original approved plan |
+| `final-transcript.md` | Final planning transcript |
+| `milestone-plan.md` | Full specification |
+| `story-tracker.md` | Current progress tracker |
+| `continuation-runbook.md` | This runbook |