Improve Cursor skills and validate component metadata

[jesseoue]

Improve the five bundled Cursor skills so each has a focused discovery trigger, a concrete example, clear tool-selection boundaries, and a purple Custom Mode badge. Align the enrichment agent and validation command with these workflows, including reuse of validated finder results and recovery from bulk timeouts.

Replace regex-only frontmatter checks with strict YAML parsing and metadata validation. CI now rejects malformed YAML, duplicate keys, incorrect names or types, empty instructions, and invalid badge colors without echoing potentially sensitive field contents. Add a manual Cursor discovery and behavior checklist, and bump the plugin to 0.1.10.

Authoring follows Cursor's built-in create-skill, create-rule, and create-subagent guidance and the current public Agent Skills documentation. The skills intentionally remain discoverable for relevant enrichment requests.

Validation: 28 tests pass, npm ci and schema validation pass, npm audit reports zero vulnerabilities, public-file checks pass, and hosted health responds HTTP 200. Authenticated Cursor behavior and UI discovery are documented manual checks, not claimed as executed.