feat(icons): 新增 34 个城市轨道交通单色图标并更新分类展示 - #6

Summary

• What does this PR change?
• Why is it needed?

Checklist

• I ran npm ci
• I ran npm run release:check
• If dependencies changed, I committed the matching package-lock.json
• I updated relevant docs / examples / prompt files when public contracts changed
• I checked that no secrets, private URLs, or unrelated generated artifacts are included
• I did not run npm publish / npm run publish:public

Validation

• Web Components usage checked (if affected)
• React adapter checked (if affected)
• Theme / dark mode checked (if affected)
• Packaging checked with npm pack --dry-run (if affected)

Screenshots / demo

Notes for maintainers

• Breaking change: yes / no
• Release note needed: yes / no
• Follow-up work: