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/workbox-build/build/inject-manifest.d.ts

@@ -0,0 +1,30 @@
+import { BuildResult, InjectManifestOptions } from './types';
+/**
+ * This method creates a list of URLs to precache, referred to as a "precache
+ * manifest", based on the options you provide.
+ *
+ * The manifest is injected into the `swSrc` file, and the placeholder string
+ * `injectionPoint` determines where in the file the manifest should go.
+ *
+ * The final service worker file, with the manifest injected, is written to
+ * disk at `swDest`.
+ *
+ * This method will not compile or bundle your `swSrc` file; it just handles
+ * injecting the manifest.
+ *
+ * ```
+ * // The following lists some common options; see the rest of the documentation
+ * // for the full set of options and defaults.
+ * const {count, size, warnings} = await injectManifest({
+ *   dontCacheBustURLsMatching: [new RegExp('...')],
+ *   globDirectory: '...',
+ *   globPatterns: ['...', '...'],
+ *   maximumFileSizeToCacheInBytes: ...,
+ *   swDest: '...',
+ *   swSrc: '...',
+ * });
+ * ```
+ *
+ * @memberof workbox-build
+ */
+export declare function injectManifest(config: InjectManifestOptions): Promise<BuildResult>;