feat: Add proof skill and optional Proof sharing in plan/brainstorm workflows (v2.37.0)

Merges feat/proof-integration with conflict resolution:
- proof skill for creating/editing/sharing markdown docs via Proof API
- "Share to Proof" added as opt-in menu option in /workflows:brainstorm Phase 4
- "Share to Proof" added as opt-in menu option in /workflows:plan Post-Generation Options
- Bumped version 2.36.0 → 2.37.0 to avoid conflict with OpenClaw/Qwen/Windsurf release

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

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

plugins/compound-engineering/CHANGELOG.md

@@ -5,6 +5,16 @@ All notable changes to the compound-engineering plugin will be documented in thi
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [2.37.0] - 2026-03-01
+
+### Added
+
+- **`proof` skill** — Create, edit, comment on, and share markdown documents via Proof's web API and local bridge. Supports document creation, track-changes suggestions, comments, and bulk rewrites. No authentication required for creating shared documents.
+- **Optional Proof sharing in `/workflows:brainstorm`** — "Share to Proof" is now a menu option in Phase 4 handoff, letting you upload the brainstorm document when you want to, rather than automatically on every run.
+- **Optional Proof sharing in `/workflows:plan`** — "Share to Proof" is now a menu option in Post-Generation Options, letting you upload the plan file on demand rather than automatically.
+
+---
+
 ## [2.36.0] - 2026-03-01
 
 ### Added