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/@babel/traverse/lib/path/inference/util.js

@@ -0,0 +1,28 @@
+"use strict";
+
+Object.defineProperty(exports, "__esModule", {
+  value: true
+});
+exports.createUnionType = createUnionType;
+var _t = require("@babel/types");
+const {
+  createFlowUnionType,
+  createTSUnionType,
+  createUnionTypeAnnotation,
+  isFlowType,
+  isTSType
+} = _t;
+function createUnionType(types) {
+  if (types.every(v => isFlowType(v))) {
+    if (createFlowUnionType) {
+      return createFlowUnionType(types);
+    }
+    return createUnionTypeAnnotation(types);
+  } else if (types.every(v => isTSType(v))) {
+    if (createTSUnionType) {
+      return createTSUnionType(types);
+    }
+  }
+}
+
+//# sourceMappingURL=util.js.map