Add PWA support to remaining Angular apps

[corvid-agent]

Moved from CorvidLabs/corvid-agent#167

Context

bw-cinema and pd-gallery have PWA support (service workers, offline fallback, manifest). Most other Angular apps do not.

Work Needed

Add PWA support to:

• weather-dashboard
• space-dashboard
• retro-arcade
• quake-tracker
• poetry-atlas
• pixel-forge
• pd-music
• pd-audiobooks

Each needs:

• @angular/pwa or manual service worker
• manifest.webmanifest with app name, icons, theme color
• Offline fallback page
• Cache strategy for API responses where appropriate