fix: proactive documentation and sprint planning automation

- doc-guardian: Hook now tracks documentation dependencies and outputs
  specific files needing updates (e.g., commands → COMMANDS-CHEATSHEET.md)
- projman: SessionStart hook now suggests /sprint-plan when open issues
  exist without milestone, and warns about unreleased CHANGELOG entries
- projman: Add /suggest-version command for semantic version recommendations
- docs: Update COMMANDS-CHEATSHEET.md with data-platform plugin (was missing)
- docs: Update CLAUDE.md with data-platform and version 4.0.0

Fixes documentation drift and lack of proactive workflow suggestions.

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

plugins/projman/commands/suggest-version.md

@@ -0,0 +1,78 @@
+# /suggest-version
+
+Analyze CHANGELOG.md and suggest appropriate semantic version bump.
+
+## Behavior
+
+1. **Read current state**:
+   - Read `CHANGELOG.md` to find current version and [Unreleased] content
+   - Read `.claude-plugin/marketplace.json` for current marketplace version
+   - Check individual plugin versions in `plugins/*/. claude-plugin/plugin.json`
+
+2. **Analyze [Unreleased] section**:
+   - Extract all entries under `### Added`, `### Changed`, `### Fixed`, `### Removed`, `### Deprecated`
+   - Categorize changes by impact
+
+3. **Apply SemVer rules**:
+
+   | Change Type | Version Bump | Indicators |
+   |-------------|--------------|------------|
+   | **MAJOR** (X.0.0) | Breaking changes | `### Removed`, `### Changed` with "BREAKING:", renamed/removed APIs |
+   | **MINOR** (x.Y.0) | New features, backwards compatible | `### Added` with new commands/plugins/features |
+   | **PATCH** (x.y.Z) | Bug fixes only | `### Fixed` only, `### Changed` for non-breaking tweaks |
+
+4. **Output recommendation**:
+   ```
+   ## Version Analysis
+
+   **Current version:** X.Y.Z
+   **[Unreleased] summary:**
+   - Added: N entries (new features/plugins)
+   - Changed: N entries (M breaking)
+   - Fixed: N entries
+   - Removed: N entries
+
+   **Recommendation:** MINOR bump → X.(Y+1).0
+   **Reason:** New features added without breaking changes
+
+   **To release:** ./scripts/release.sh X.Y.Z
+   ```
+
+5. **Check version sync**:
+   - Compare marketplace version with individual plugin versions
+   - Warn if plugins are out of sync (e.g., marketplace 4.0.0 but projman 3.1.0)
+
+## Examples
+
+**Output when MINOR bump needed:**
+```
+## Version Analysis
+
+**Current version:** 4.0.0
+**[Unreleased] summary:**
+- Added: 3 entries (new command, hook improvement, workflow example)
+- Changed: 1 entry (0 breaking)
+- Fixed: 2 entries
+
+**Recommendation:** MINOR bump → 4.1.0
+**Reason:** New features (Added section) without breaking changes
+
+**To release:** ./scripts/release.sh 4.1.0
+```
+
+**Output when nothing to release:**
+```
+## Version Analysis
+
+**Current version:** 4.0.0
+**[Unreleased] summary:** Empty - no pending changes
+
+**Recommendation:** No release needed
+```
+
+## Integration
+
+This command helps maintain proper versioning workflow:
+- Run after completing a sprint to determine version bump
+- Run before `/sprint-close` to ensure version is updated
+- Integrates with `./scripts/release.sh` for actual release execution