fix(skills): remove phantom resource references and fix CoC links (#447)

Remove references to non-existent resource files (references/, assets/,
scripts/, examples/) from 115 skill SKILL.md files. These sections
pointed to directories and files that were never created, causing
confusion when users install skills.

Also fix broken Code of Conduct links in issue templates to use
absolute GitHub URLs instead of relative paths that 404.

plugins/framework-migration/skills/angular-migration/SKILL.md

@@ -384,32 +384,3 @@ Phase 4: Cleanup (1-2 weeks)
 - Optimize bundle
 - Final testing
 ```
-
-## Resources
-
-- **references/hybrid-mode.md**: Hybrid app patterns
-- **references/component-migration.md**: Component conversion guide
-- **references/dependency-injection.md**: DI migration strategies
-- **references/routing.md**: Routing migration
-- **assets/hybrid-bootstrap.ts**: Hybrid app template
-- **assets/migration-timeline.md**: Project planning
-- **scripts/analyze-angular-app.sh**: App analysis script
-
-## Best Practices
-
-1. **Start with Services**: Migrate services first (easier)
-2. **Incremental Approach**: Feature-by-feature migration
-3. **Test Continuously**: Test at every step
-4. **Use TypeScript**: Migrate to TypeScript early
-5. **Follow Style Guide**: Angular style guide from day 1
-6. **Optimize Later**: Get it working, then optimize
-7. **Document**: Keep migration notes
-
-## Common Pitfalls
-
-- Not setting up hybrid app correctly
-- Migrating UI before logic
-- Ignoring change detection differences
-- Not handling scope properly
-- Mixing patterns (AngularJS + Angular)
-- Inadequate testing