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/spread.js

@@ -0,0 +1,63 @@
+var apply = require('./_apply'),
+    arrayPush = require('./_arrayPush'),
+    baseRest = require('./_baseRest'),
+    castSlice = require('./_castSlice'),
+    toInteger = require('./toInteger');
+
+/** Error message constants. */
+var FUNC_ERROR_TEXT = 'Expected a function';
+
+/* Built-in method references for those with the same name as other `lodash` methods. */
+var nativeMax = Math.max;
+
+/**
+ * Creates a function that invokes `func` with the `this` binding of the
+ * create function and an array of arguments much like
+ * [`Function#apply`](http://www.ecma-international.org/ecma-262/7.0/#sec-function.prototype.apply).
+ *
+ * **Note:** This method is based on the
+ * [spread operator](https://mdn.io/spread_operator).
+ *
+ * @static
+ * @memberOf _
+ * @since 3.2.0
+ * @category Function
+ * @param {Function} func The function to spread arguments over.
+ * @param {number} [start=0] The start position of the spread.
+ * @returns {Function} Returns the new function.
+ * @example
+ *
+ * var say = _.spread(function(who, what) {
+ *   return who + ' says ' + what;
+ * });
+ *
+ * say(['fred', 'hello']);
+ * // => 'fred says hello'
+ *
+ * var numbers = Promise.all([
+ *   Promise.resolve(40),
+ *   Promise.resolve(36)
+ * ]);
+ *
+ * numbers.then(_.spread(function(x, y) {
+ *   return x + y;
+ * }));
+ * // => a Promise of 76
+ */
+function spread(func, start) {
+  if (typeof func != 'function') {
+    throw new TypeError(FUNC_ERROR_TEXT);
+  }
+  start = start == null ? 0 : nativeMax(toInteger(start), 0);
+  return baseRest(function(args) {
+    var array = args[start],
+        otherArgs = castSlice(args, 0, start);
+
+    if (array) {
+      arrayPush(otherArgs, array);
+    }
+    return apply(func, this, otherArgs);
+  });
+}
+
+module.exports = spread;