Polish extension provenance and settings

[brsbl]

Summary

• show Included provenance and provider logos for plugin-bundled skills
• keep plugin configuration in Settings regardless of Tools Hub
• keep plugin detail focused on capabilities with accessible long-description disclosure
• render BB Official browse entries inline as standard cards with installed states

Verification

• 102 focused tests passed
• pnpm exec turbo run typecheck --filter=@bb/app
• branch dev app: provider menu, skills provenance, official cards, Settings with Tools Hub on/off, long capability expand/collapse