feat: the server and the windows can ask which parts a custom system …

[over2take]

…uses

runtime.partIn(system, part) on the server, and partOn / useParts in the browser (sheets/parts.ts), answer whether a part of the app (the bank, shops, vehicles, cyberware...) is on while a system runs. A built-in system, an unknown id and a custom system not loaded yet have every part on, so each place keeps its own rule; only a published custom system can turn one off. A misspelled part throws on the server rather than quietly reading as on.

The browser kept a custom system's words from its render copy but dropped its parts; the template now carries both. useWords and useParts share one loading hook. Nothing is hidden yet: the pieces that follow add partOn beside each place's own check.

Summary

Test plan

• Tested locally
• Tests pass

Pre-merge checklist

Code quality:

• Code follows project style
• No breaking changes (or clearly documented)
• No console errors or warnings

Version & Release:

• Version bumped? If releasing to users, update:
  • frontend/package.json version
  • docker-compose.yml APP_VERSION
  • CHANGELOG.md with release notes
• GitHub Actions will auto-tag Docker images with the new version

Before merging to main:

• All tests passing
• PR reviewed and approved
• Branch is up to date with main
• No merge conflicts

Related issues