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/pr-review/commands/pr-diff.md

@@ -1,4 +1,10 @@
-# /pr-diff - Annotated PR Diff Viewer
+---
+name: pr diff
+description: Formatted diff with inline review comments
+agent: coordinator
+---
+
+# /pr diff - Annotated PR Diff Viewer
 
 ## Visual Output
 
@@ -13,7 +19,7 @@ Display header: `PR-REVIEW - Diff Viewer`
 ## Usage
 
 ```
-/pr-diff <pr-number> [--repo owner/repo] [--context <n>] [--no-comments] [--file <pattern>]
+/pr diff <pr-number> [--repo owner/repo] [--context <n>] [--no-comments] [--file <pattern>]
 ```
 
 ## Workflow
@@ -43,6 +49,6 @@ Use annotated diff format from `skills/output-formats.md`
 
 | Command | Purpose |
 |---------|---------|
-| `/pr-summary` | Quick overview |
-| `/pr-review` | Full review |
-| `/pr-findings` | Filter findings |
+| `/pr summary` | Quick overview |
+| `/pr review` | Full review |
+| `/pr findings` | Filter findings |