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/@babel/runtime/helpers/dispose.js

@@ -0,0 +1,28 @@
+function dispose_SuppressedError(r, e) {
+  return "undefined" != typeof SuppressedError ? dispose_SuppressedError = SuppressedError : (dispose_SuppressedError = function dispose_SuppressedError(r, e) {
+    this.suppressed = e, this.error = r, this.stack = Error().stack;
+  }, dispose_SuppressedError.prototype = Object.create(Error.prototype, {
+    constructor: {
+      value: dispose_SuppressedError,
+      writable: !0,
+      configurable: !0
+    }
+  })), new dispose_SuppressedError(r, e);
+}
+function _dispose(r, e, s) {
+  function next() {
+    for (; r.length > 0;) try {
+      var o = r.pop(),
+        p = o.d.call(o.v);
+      if (o.a) return Promise.resolve(p).then(next, err);
+    } catch (r) {
+      return err(r);
+    }
+    if (s) throw e;
+  }
+  function err(r) {
+    return e = s ? new dispose_SuppressedError(e, r) : r, s = !0, next();
+  }
+  return next();
+}
+module.exports = _dispose, module.exports.__esModule = true, module.exports["default"] = module.exports;