feat: import 35 skills from affaan-m/everything-claude-code

- Add 9 agent skills (cc-agent-*)
- Add 10 command skills (cc-cmd-*)
- Add 8 skill files (cc-skill-*)
- Add 8 rule skills (cc-rule-*)
- Update README.md skill count from 225 to 260
- Add new skills to Full Skill Registry
- Add credit to affaan-m in Credits section
- Regenerate skills_index.json

Source: https://github.com/affaan-m/everything-claude-code
Author attribution: affaan-m, version 1.0

skills/cc-cmd-test-coverage/SKILL.md

@@ -0,0 +1,34 @@
+---
+name: cc-cmd-test-coverage
+description: Test Coverage
+author: affaan-m
+version: "1.0"
+---
+
+# Test Coverage
+
+Analyze test coverage and generate missing tests:
+
+1. Run tests with coverage: npm test --coverage or pnpm test --coverage
+
+2. Analyze coverage report (coverage/coverage-summary.json)
+
+3. Identify files below 80% coverage threshold
+
+4. For each under-covered file:
+   - Analyze untested code paths
+   - Generate unit tests for functions
+   - Generate integration tests for APIs
+   - Generate E2E tests for critical flows
+
+5. Verify new tests pass
+
+6. Show before/after coverage metrics
+
+7. Ensure project reaches 80%+ overall coverage
+
+Focus on:
+- Happy path scenarios
+- Error handling
+- Edge cases (null, undefined, empty)
+- Boundary conditions