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/_baseGetAllKeys.js

@@ -0,0 +1,20 @@
+var arrayPush = require('./_arrayPush'),
+    isArray = require('./isArray');
+
+/**
+ * The base implementation of `getAllKeys` and `getAllKeysIn` which uses
+ * `keysFunc` and `symbolsFunc` to get the enumerable property names and
+ * symbols of `object`.
+ *
+ * @private
+ * @param {Object} object The object to query.
+ * @param {Function} keysFunc The function to get the keys of `object`.
+ * @param {Function} symbolsFunc The function to get the symbols of `object`.
+ * @returns {Array} Returns the array of property names and symbols.
+ */
+function baseGetAllKeys(object, keysFunc, symbolsFunc) {
+  var result = keysFunc(object);
+  return isArray(object) ? result : arrayPush(result, symbolsFunc(object));
+}
+
+module.exports = baseGetAllKeys;