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/vite-plugin-pwa/dist/chunk-SF7B43FO.js

@@ -0,0 +1,54 @@
+// src/pwa-assets/utils.ts
+function mapLink(includeId, link) {
+  const linkObject = {
+    href: link.href,
+    rel: link.rel
+  };
+  if (includeId && link.id)
+    linkObject.id = link.id;
+  if ("media" in link && link.media)
+    linkObject.media = link.media;
+  linkObject.href = link.href;
+  if ("sizes" in link && link.sizes)
+    linkObject.sizes = link.sizes;
+  if ("type" in link && link.type)
+    linkObject.type = link.type;
+  return linkObject;
+}
+function extractIcons(instructions) {
+  const icons = {
+    favicon: {},
+    transparent: {},
+    maskable: {},
+    apple: {},
+    appleSplashScreen: {}
+  };
+  if (instructions) {
+    Array.from(Object.values(instructions.favicon)).forEach(({ buffer: _buffer, ...rest }) => {
+      if (rest.url)
+        icons.favicon[rest.url] = { ...rest };
+    });
+    Array.from(Object.values(instructions.transparent)).forEach(({ buffer: _buffer, ...rest }) => {
+      if (rest.url)
+        icons.transparent[rest.url] = { ...rest };
+    });
+    Array.from(Object.values(instructions.maskable)).forEach(({ buffer: _buffer, ...rest }) => {
+      if (rest.url)
+        icons.maskable[rest.url] = { ...rest };
+    });
+    Array.from(Object.values(instructions.apple)).forEach(({ buffer: _buffer, ...rest }) => {
+      if (rest.url)
+        icons.apple[rest.url] = { ...rest };
+    });
+    Array.from(Object.values(instructions.appleSplashScreen)).forEach(({ buffer: _buffer, ...rest }) => {
+      if (rest.url)
+        icons.appleSplashScreen[rest.url] = { ...rest };
+    });
+  }
+  return icons;
+}
+
+export {
+  mapLink,
+  extractIcons
+};