Add PWA manifest, world bands with night mode, milestones, touch drag, and lab QoL

- World view: three stacked sky/land/sea bands, night palette 22h-5h
- manifest.webmanifest + theme-color; sw cache bumped to v2
- Touch drag & drop via pointer events (mouse DnD kept)
- Milestone toasts at 25/50/75/100% discovery
- Search matches name, description, and category
- Lab: Enter to combine, clear-slots button, last-5 combo chips
- Secret discoveries: full-screen flash + golden card border
- Category accent colors on cards and filter chips
- Serif display type for results, journal titles, daily goal
- Desktop sticky creation panel; mobile sheet mid snap point;
  compact layout for short landscape screens

first commit

first commit