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/wrapNativeSuper.js

@@ -0,0 +1,27 @@
+var getPrototypeOf = require("./getPrototypeOf.js");
+var setPrototypeOf = require("./setPrototypeOf.js");
+var isNativeFunction = require("./isNativeFunction.js");
+var construct = require("./construct.js");
+function _wrapNativeSuper(t) {
+  var r = "function" == typeof Map ? new Map() : void 0;
+  return module.exports = _wrapNativeSuper = function _wrapNativeSuper(t) {
+    if (null === t || !isNativeFunction(t)) return t;
+    if ("function" != typeof t) throw new TypeError("Super expression must either be null or a function");
+    if (void 0 !== r) {
+      if (r.has(t)) return r.get(t);
+      r.set(t, Wrapper);
+    }
+    function Wrapper() {
+      return construct(t, arguments, getPrototypeOf(this).constructor);
+    }
+    return Wrapper.prototype = Object.create(t.prototype, {
+      constructor: {
+        value: Wrapper,
+        enumerable: !1,
+        writable: !0,
+        configurable: !0
+      }
+    }), setPrototypeOf(Wrapper, t);
+  }, module.exports.__esModule = true, module.exports["default"] = module.exports, _wrapNativeSuper(t);
+}
+module.exports = _wrapNativeSuper, module.exports.__esModule = true, module.exports["default"] = module.exports;