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/helper-compilation-targets/lib/targets.js

@@ -0,0 +1,28 @@
+"use strict";
+
+Object.defineProperty(exports, "__esModule", {
+  value: true
+});
+exports.unreleasedLabels = exports.browserNameMap = void 0;
+const unreleasedLabels = exports.unreleasedLabels = {
+  safari: "tp"
+};
+const browserNameMap = exports.browserNameMap = {
+  and_chr: "chrome",
+  and_ff: "firefox",
+  android: "android",
+  chrome: "chrome",
+  edge: "edge",
+  firefox: "firefox",
+  ie: "ie",
+  ie_mob: "ie",
+  ios_saf: "ios",
+  node: "node",
+  deno: "deno",
+  op_mob: "opera_mobile",
+  opera: "opera",
+  safari: "safari",
+  samsung: "samsung"
+};
+
+//# sourceMappingURL=targets.js.map