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/lodash/_getSymbolsIn.js

@@ -0,0 +1,25 @@
+var arrayPush = require('./_arrayPush'),
+    getPrototype = require('./_getPrototype'),
+    getSymbols = require('./_getSymbols'),
+    stubArray = require('./stubArray');
+
+/* Built-in method references for those with the same name as other `lodash` methods. */
+var nativeGetSymbols = Object.getOwnPropertySymbols;
+
+/**
+ * Creates an array of the own and inherited enumerable symbols of `object`.
+ *
+ * @private
+ * @param {Object} object The object to query.
+ * @returns {Array} Returns the array of symbols.
+ */
+var getSymbolsIn = !nativeGetSymbols ? stubArray : function(object) {
+  var result = [];
+  while (object) {
+    arrayPush(result, getSymbols(object));
+    object = getPrototype(object);
+  }
+  return result;
+};
+
+module.exports = getSymbolsIn;