chore: remove deprecated workflows:* skill aliases (#284)

* docs: capture codex skill prompt model

* fix: align codex workflow conversion

* chore: remove deprecated workflows:* skill aliases

The workflows:brainstorm, workflows:plan, workflows:work, workflows:review,
and workflows:compound aliases have been deprecated long enough. Remove them
and update skill counts (46 → 41) across plugin.json, marketplace.json,
README, and CLAUDE.md.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Trevin Chow <trevin@trevinchow.com>
Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

.claude-plugin/marketplace.json

@@ -11,7 +11,7 @@
   "plugins": [
     {
       "name": "compound-engineering",
-      "description": "AI-powered development tools that get smarter with every use. Make each unit of engineering work easier than the last. Includes 28 specialized agents and 46 skills.",
+      "description": "AI-powered development tools that get smarter with every use. Make each unit of engineering work easier than the last. Includes 28 specialized agents and 41 skills.",
       "version": "2.40.0",
       "author": {
         "name": "Kieran Klaassen",