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/async/whilst.js

@@ -0,0 +1,78 @@
+'use strict';
+
+Object.defineProperty(exports, "__esModule", {
+    value: true
+});
+
+var _onlyOnce = require('./internal/onlyOnce.js');
+
+var _onlyOnce2 = _interopRequireDefault(_onlyOnce);
+
+var _wrapAsync = require('./internal/wrapAsync.js');
+
+var _wrapAsync2 = _interopRequireDefault(_wrapAsync);
+
+var _awaitify = require('./internal/awaitify.js');
+
+var _awaitify2 = _interopRequireDefault(_awaitify);
+
+function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
+
+/**
+ * Repeatedly call `iteratee`, while `test` returns `true`. Calls `callback` when
+ * stopped, or an error occurs.
+ *
+ * @name whilst
+ * @static
+ * @memberOf module:ControlFlow
+ * @method
+ * @category Control Flow
+ * @param {AsyncFunction} test - asynchronous truth test to perform before each
+ * execution of `iteratee`. Invoked with (callback).
+ * @param {AsyncFunction} iteratee - An async function which is called each time
+ * `test` passes. Invoked with (callback).
+ * @param {Function} [callback] - A callback which is called after the test
+ * function has failed and repeated execution of `iteratee` has stopped. `callback`
+ * will be passed an error and any arguments passed to the final `iteratee`'s
+ * callback. Invoked with (err, [results]);
+ * @returns {Promise} a promise, if no callback is passed
+ * @example
+ *
+ * var count = 0;
+ * async.whilst(
+ *     function test(cb) { cb(null, count < 5); },
+ *     function iter(callback) {
+ *         count++;
+ *         setTimeout(function() {
+ *             callback(null, count);
+ *         }, 1000);
+ *     },
+ *     function (err, n) {
+ *         // 5 seconds have passed, n = 5
+ *     }
+ * );
+ */
+function whilst(test, iteratee, callback) {
+    callback = (0, _onlyOnce2.default)(callback);
+    var _fn = (0, _wrapAsync2.default)(iteratee);
+    var _test = (0, _wrapAsync2.default)(test);
+    var results = [];
+
+    function next(err, ...rest) {
+        if (err) return callback(err);
+        results = rest;
+        if (err === false) return;
+        _test(check);
+    }
+
+    function check(err, truth) {
+        if (err) return callback(err);
+        if (err === false) return;
+        if (!truth) return callback(null, ...results);
+        _fn(next);
+    }
+
+    return _test(check);
+}
+exports.default = (0, _awaitify2.default)(whilst, 3);
+module.exports = exports.default;