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/template/lib/string.js

@@ -0,0 +1,20 @@
+"use strict";
+
+Object.defineProperty(exports, "__esModule", {
+  value: true
+});
+exports.default = stringTemplate;
+var _options = require("./options.js");
+var _parse = require("./parse.js");
+var _populate = require("./populate.js");
+function stringTemplate(formatter, code, opts) {
+  code = formatter.code(code);
+  let metadata;
+  return arg => {
+    const replacements = (0, _options.normalizeReplacements)(arg);
+    if (!metadata) metadata = (0, _parse.default)(formatter, code, opts);
+    return formatter.unwrap((0, _populate.default)(metadata, replacements));
+  };
+}
+
+//# sourceMappingURL=string.js.map