feat(skills): add codehealth-mcp skill and CodeScene MCP config (#2077)

* feat(skills): add codehealth-mcp skill and CodeScene MCP config

* docs(skills): add When to Use, How It Works, and Examples sections

* docs(skills): clarify MCP opt-in, data boundaries, and offline behavior

Address security review on PR #2077: no bundled credentials, document what
tools read locally, failure behavior when MCP is unavailable, and README
wording that Code Health MCP is optional and not enabled by default.

Co-authored-by: Cursor <cursoragent@cursor.com>

---------

Co-authored-by: adnasalk-notus <adna.salkovic@notus.hr>
Co-authored-by: Cursor <cursoragent@cursor.com>

README.md

@@ -608,6 +608,7 @@ ECC/
 |   |-- perl-testing/              # Perl TDD with Test2::V0, prove, Devel::Cover (NEW)
 |   |-- autonomous-loops/           # Autonomous loop patterns: sequential pipelines, PR loops, DAG orchestration (NEW)
 |   |-- plankton-code-quality/      # Write-time code quality enforcement with Plankton hooks (NEW)
+|   |-- codehealth-mcp/             # Optional CodeScene Code Health MCP skill (opt-in; not enabled by default) (NEW)
 |
 |-- commands/         # Maintained slash-entry compatibility; prefer skills/
 |   |-- plan.md             # /plan - Implementation planning
@@ -1348,6 +1349,7 @@ Canonical Anthropic skills such as `claude-api`, `frontend-design`, and `skill-c
 | brand-voice | Source-derived writing style profiles from real content |
 | bun-runtime | Bun as runtime, package manager, bundler, and test runner |
 | coding-standards | Universal coding standards |
+| codehealth-mcp | Optional — Code Health MCP (opt-in server + token); structural review and commit/PR gates |
 | content-engine | Platform-native social content and repurposing |
 | crosspost | Multi-platform content distribution across X, LinkedIn, Threads |
 | deep-research | Multi-source research with synthesis and source attribution |