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-node/dist/utils.d.ts

@@ -0,0 +1,31 @@
+import { N as Nullable, A as Arrayable } from './index-z0R8hVRu.js';
+import './trace-mapping.d-DLVdEqOp.js';
+
+declare const isWindows: boolean;
+declare function slash(str: string): string;
+declare const VALID_ID_PREFIX = "/@id/";
+declare function normalizeRequestId(id: string, base?: string): string;
+declare function cleanUrl(url: string): string;
+declare function isInternalRequest(id: string): boolean;
+declare function normalizeModuleId(id: string): string;
+declare function isPrimitive(v: any): boolean;
+declare function toFilePath(id: string, root: string): {
+    path: string;
+    exists: boolean;
+};
+declare function isNodeBuiltin(id: string): boolean;
+/**
+ * Convert `Arrayable<T>` to `Array<T>`
+ *
+ * @category Array
+ */
+declare function toArray<T>(array?: Nullable<Arrayable<T>>): Array<T>;
+declare function getCachedData<T>(cache: Map<string, T>, basedir: string, originalBasedir: string): NonNullable<T> | undefined;
+declare function setCacheData<T>(cache: Map<string, T>, data: T, basedir: string, originalBasedir: string): void;
+declare function withTrailingSlash(path: string): string;
+declare function createImportMetaEnvProxy(): NodeJS.ProcessEnv;
+declare function findNearestPackageData(basedir: string): Promise<{
+    type?: 'module' | 'commonjs';
+}>;
+
+export { VALID_ID_PREFIX, cleanUrl, createImportMetaEnvProxy, findNearestPackageData, getCachedData, isInternalRequest, isNodeBuiltin, isPrimitive, isWindows, normalizeModuleId, normalizeRequestId, setCacheData, slash, toArray, toFilePath, withTrailingSlash };