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/_hashGet.js

@@ -0,0 +1,30 @@
+var nativeCreate = require('./_nativeCreate');
+
+/** Used to stand-in for `undefined` hash values. */
+var HASH_UNDEFINED = '__lodash_hash_undefined__';
+
+/** Used for built-in method references. */
+var objectProto = Object.prototype;
+
+/** Used to check objects for own properties. */
+var hasOwnProperty = objectProto.hasOwnProperty;
+
+/**
+ * Gets the hash value for `key`.
+ *
+ * @private
+ * @name get
+ * @memberOf Hash
+ * @param {string} key The key of the value to get.
+ * @returns {*} Returns the entry value.
+ */
+function hashGet(key) {
+  var data = this.__data__;
+  if (nativeCreate) {
+    var result = data[key];
+    return result === HASH_UNDEFINED ? undefined : result;
+  }
+  return hasOwnProperty.call(data, key) ? data[key] : undefined;
+}
+
+module.exports = hashGet;