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/_arrayLikeKeys.js

@@ -0,0 +1,49 @@
+var baseTimes = require('./_baseTimes'),
+    isArguments = require('./isArguments'),
+    isArray = require('./isArray'),
+    isBuffer = require('./isBuffer'),
+    isIndex = require('./_isIndex'),
+    isTypedArray = require('./isTypedArray');
+
+/** Used for built-in method references. */
+var objectProto = Object.prototype;
+
+/** Used to check objects for own properties. */
+var hasOwnProperty = objectProto.hasOwnProperty;
+
+/**
+ * Creates an array of the enumerable property names of the array-like `value`.
+ *
+ * @private
+ * @param {*} value The value to query.
+ * @param {boolean} inherited Specify returning inherited property names.
+ * @returns {Array} Returns the array of property names.
+ */
+function arrayLikeKeys(value, inherited) {
+  var isArr = isArray(value),
+      isArg = !isArr && isArguments(value),
+      isBuff = !isArr && !isArg && isBuffer(value),
+      isType = !isArr && !isArg && !isBuff && isTypedArray(value),
+      skipIndexes = isArr || isArg || isBuff || isType,
+      result = skipIndexes ? baseTimes(value.length, String) : [],
+      length = result.length;
+
+  for (var key in value) {
+    if ((inherited || hasOwnProperty.call(value, key)) &&
+        !(skipIndexes && (
+           // Safari 9 has enumerable `arguments.length` in strict mode.
+           key == 'length' ||
+           // Node.js 0.10 has enumerable non-index properties on buffers.
+           (isBuff && (key == 'offset' || key == 'parent')) ||
+           // PhantomJS 2 has enumerable non-index properties on typed arrays.
+           (isType && (key == 'buffer' || key == 'byteLength' || key == 'byteOffset')) ||
+           // Skip index properties.
+           isIndex(key, length)
+        ))) {
+      result.push(key);
+    }
+  }
+  return result;
+}
+
+module.exports = arrayLikeKeys;