feat(marketplace): command consolidation + 8 new plugins (v8.1.0 → v9.0.0) [BREAKING]

Phase 1b: Rename all ~94 commands across 12 plugins to /<noun> <action>
sub-command pattern. Git-flow consolidated from 8→5 commands (commit
variants absorbed into --push/--merge/--sync flags). Dispatch files,
name: frontmatter, and cross-reference updates for all plugins.

Phase 2: Design documents for 8 new plugins in docs/designs/.

Phase 3: Scaffold 8 new plugins — saas-api-platform, saas-db-migrate,
saas-react-platform, saas-test-pilot, data-seed, ops-release-manager,
ops-deploy-pipeline, debug-mcp. Each with plugin.json, commands, agents,
skills, README, and claude-md-integration. Marketplace grows from 12→20.

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

plugins/git-flow/commands/gitflow-branch-cleanup.md

@@ -0,0 +1,49 @@
+---
+name: gitflow branch-cleanup
+description: Remove merged and stale branches locally and optionally on remote
+agent: git-assistant
+---
+
+# /gitflow branch-cleanup - Clean Merged and Stale Branches
+
+## Skills
+
+- skills/visual-header.md
+- skills/git-safety.md
+- skills/sync-workflow.md
+- skills/environment-variables.md
+
+## Purpose
+
+Remove branches that have been merged OR whose remote tracking branch no longer exists.
+
+## Parameters
+
+| Parameter | Description |
+|-----------|-------------|
+| `--dry-run` | Preview without deleting |
+| `--remote` | Also delete remote branches |
+| `--stale-only` | Only delete stale branches (upstream gone) |
+
+## Workflow
+
+1. **Display header** - Show GIT-FLOW Branch Cleanup header
+2. **Prune remote refs** - `git fetch --prune`
+3. **Find merged branches** - `git branch --merged <base-branch>`
+4. **Find stale branches** - `git branch -vv | grep ': gone]'`
+5. **Exclude protected** - Never delete protected branches (per git-safety.md)
+6. **Present findings** - Show merged, stale, and protected lists
+7. **Confirm deletion** - Options: all, merged only, stale only, pick, cancel
+8. **Execute cleanup** - Delete selected branches
+9. **Report** - Show deletion summary
+
+## Output
+
+```
+Cleaned up:
+  Local (merged): 3 branches deleted
+  Local (stale): 2 branches deleted
+  Remote: 2 branches deleted
+
+Repository is tidy!
+```