chore: npm publish setup, fallback docs, release workflow (fixes #49)

- package.json: yaml in devDependencies, repo url/bin from npm pkg fix
- README, GETTING_STARTED, FAQ: fallback npx github:sickn33/antigravity-awesome-skills on 404
- publish-npm.yml: workflow on release published + workflow_dispatch
- MAINTENANCE: bump package.json, publish to npm (manual + NPM_TOKEN CI)
- release_cycle.sh: catalog step, version check, npm publish reminder
- ISSUE_49_COMMENT.md: suggested reply for issue #49

README.md

@@ -155,6 +155,8 @@ npx antigravity-awesome-skills --path ./my-skills
 
 Run `npx antigravity-awesome-skills --help` for all options. If the directory already exists, the installer runs `git pull` to update.
 
+> **If you see a 404 error:** the package may not be published to npm yet. Use: `npx github:sickn33/antigravity-awesome-skills`
+
 ### Option B: git clone
 
 ```bash