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/rollup/dist/shared/fsevents-importer.js

@@ -0,0 +1,37 @@
+/*
+  @license
+	Rollup.js v4.59.0
+	Sun, 22 Feb 2026 07:31:53 GMT - commit ae846957f109690a866cc3e4c073613c338d3476
+
+	https://github.com/rollup/rollup
+
+	Released under the MIT License.
+*/
+'use strict';
+
+let fsEvents;
+let fsEventsImportError;
+async function loadFsEvents() {
+    try {
+        ({ default: fsEvents } = await import('fsevents'));
+    }
+    catch (error) {
+        fsEventsImportError = error;
+    }
+}
+// A call to this function will be injected into the chokidar code
+function getFsEvents() {
+    if (fsEventsImportError)
+        throw fsEventsImportError;
+    return fsEvents;
+}
+
+const fseventsImporter = /*#__PURE__*/Object.defineProperty({
+    __proto__: null,
+    getFsEvents,
+    loadFsEvents
+}, Symbol.toStringTag, { value: 'Module' });
+
+exports.fseventsImporter = fseventsImporter;
+exports.loadFsEvents = loadFsEvents;
+//# sourceMappingURL=fsevents-importer.js.map