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/traverse/lib/cache.js

@@ -0,0 +1,37 @@
+"use strict";
+
+Object.defineProperty(exports, "__esModule", {
+  value: true
+});
+exports.clear = clear;
+exports.clearPath = clearPath;
+exports.clearScope = clearScope;
+exports.getCachedPaths = getCachedPaths;
+exports.getOrCreateCachedPaths = getOrCreateCachedPaths;
+exports.scope = exports.path = void 0;
+let pathsCache = exports.path = new WeakMap();
+let scope = exports.scope = new WeakMap();
+function clear() {
+  clearPath();
+  clearScope();
+}
+function clearPath() {
+  exports.path = pathsCache = new WeakMap();
+}
+function clearScope() {
+  exports.scope = scope = new WeakMap();
+}
+function getCachedPaths(path) {
+  const {
+    parent,
+    parentPath
+  } = path;
+  return pathsCache.get(parent);
+}
+function getOrCreateCachedPaths(node, parentPath) {
+  let paths = pathsCache.get(node);
+  if (!paths) pathsCache.set(node, paths = new Map());
+  return paths;
+}
+
+//# sourceMappingURL=cache.js.map