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/assignWith.js

@@ -0,0 +1,37 @@
+var copyObject = require('./_copyObject'),
+    createAssigner = require('./_createAssigner'),
+    keys = require('./keys');
+
+/**
+ * This method is like `_.assign` except that it accepts `customizer`
+ * which is invoked to produce the assigned values. If `customizer` returns
+ * `undefined`, assignment is handled by the method instead. The `customizer`
+ * is invoked with five arguments: (objValue, srcValue, key, object, source).
+ *
+ * **Note:** This method mutates `object`.
+ *
+ * @static
+ * @memberOf _
+ * @since 4.0.0
+ * @category Object
+ * @param {Object} object The destination object.
+ * @param {...Object} sources The source objects.
+ * @param {Function} [customizer] The function to customize assigned values.
+ * @returns {Object} Returns `object`.
+ * @see _.assignInWith
+ * @example
+ *
+ * function customizer(objValue, srcValue) {
+ *   return _.isUndefined(objValue) ? srcValue : objValue;
+ * }
+ *
+ * var defaults = _.partialRight(_.assignWith, customizer);
+ *
+ * defaults({ 'a': 1 }, { 'b': 2 }, { 'a': 3 });
+ * // => { 'a': 1, 'b': 2 }
+ */
+var assignWith = createAssigner(function(object, source, srcIndex, customizer) {
+  copyObject(source, keys(source), object, customizer);
+});
+
+module.exports = assignWith;