Add progressive web app companion for cross-platform access

Vite + TypeScript PWA that mirrors the Android app's core features:
- Pre-processed shelter data (build-time UTM33N→WGS84 conversion)
- Leaflet map with shelter markers, user location, and offline tiles
- Canvas compass arrow (ported from DirectionArrowView.kt)
- IndexedDB shelter cache with 7-day staleness check
- Service worker with CacheFirst tiles and precached app shell
- i18n for en, nb, nn (ported from Android strings.xml)
- iOS/Android compass handling with low-pass filter
- Respects user map interaction (no auto-snap on pan/zoom)
- Build revision cache-breaker for reliable SW updates

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

pwa/node_modules/jake/lib/task/index.js

@@ -0,0 +1,9 @@
+
+let Task = require('./task').Task;
+let FileTask = require('./file_task').FileTask;
+let DirectoryTask = require('./directory_task').DirectoryTask;
+
+exports.Task = Task;
+exports.FileTask = FileTask;
+exports.DirectoryTask = DirectoryTask;
+