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/tinypool/dist/index.d.ts

@@ -0,0 +1,195 @@
+/// <reference types="node" />
+import { MessagePort, TransferListItem } from "node:worker_threads";
+import { EventEmitterAsyncResource } from "node:events";
+
+//#region src/common.d.ts
+/** Channel for communicating between main thread and workers */
+/** Channel for communicating between main thread and workers */
+interface TinypoolChannel {
+  /** Workers subscribing to messages */
+  onMessage?: (callback: (message: any) => void) => void;
+  /** Called with worker's messages */
+  postMessage?: (message: any) => void;
+  /** Called when channel can be closed */
+  onClose?: () => void;
+}
+interface TinypoolWorker {
+  runtime: string;
+  initialize(options: {
+    env?: Record<string, string>;
+    argv?: string[];
+    execArgv?: string[];
+    resourceLimits?: any;
+    workerData: TinypoolData;
+    trackUnmanagedFds?: boolean;
+  }): void;
+  terminate(): Promise<any>;
+  postMessage(message: any, transferListItem?: TransferListItem[]): void;
+  setChannel?: (channel: TinypoolChannel) => void;
+  on(event: string, listener: (...args: any[]) => void): void;
+  once(event: string, listener: (...args: any[]) => void): void;
+  emit(event: string, ...data: any[]): void;
+  ref?: () => void;
+  unref?: () => void;
+  threadId: number;
+}
+/**
+ * Tinypool's internal messaging between main thread and workers.
+ * - Utilizers can use `__tinypool_worker_message__` property to identify
+ *   these messages and ignore them.
+ */
+interface TinypoolWorkerMessage<T extends 'port' | 'pool' = 'port' | 'pool'> {
+  __tinypool_worker_message__: true;
+  source: T;
+}
+interface StartupMessage {
+  filename: string | null;
+  name: string;
+  port: MessagePort;
+  sharedBuffer: Int32Array;
+  useAtomics: boolean;
+}
+interface RequestMessage {
+  taskId: number;
+  task: any;
+  filename: string;
+  name: string;
+}
+interface ReadyMessage {
+  ready: true;
+}
+interface ResponseMessage {
+  taskId: number;
+  result: any;
+  error: unknown | null;
+  usedMemory: number;
+}
+interface TinypoolPrivateData {
+  workerId: number;
+}
+type TinypoolData = [TinypoolPrivateData, any];
+declare const kTransferable: unique symbol;
+declare const kValue: unique symbol;
+declare const kQueueOptions: unique symbol;
+declare function isTransferable(value: any): boolean;
+declare function isMovable(value: any): boolean;
+declare function markMovable(value: object): void;
+interface Transferable {
+  readonly [kTransferable]: object;
+  readonly [kValue]: object;
+}
+interface Task {
+  readonly [kQueueOptions]: object | null;
+  cancel(): void;
+}
+interface TaskQueue {
+  readonly size: number;
+  shift(): Task | null;
+  remove(task: Task): void;
+  push(task: Task): void;
+  cancel(): void;
+}
+declare function isTaskQueue(value: any): boolean;
+declare const kRequestCountField = 0;
+declare const kResponseCountField = 1;
+declare const kFieldCount = 2; //#endregion
+//#region src/index.d.ts
+declare global {
+  namespace NodeJS {
+    interface Process {
+      __tinypool_state__: {
+        isTinypoolWorker: boolean;
+        isWorkerThread?: boolean;
+        isChildProcess?: boolean;
+        workerData: any;
+        workerId: number;
+      };
+    }
+  }
+}
+interface AbortSignalEventTargetAddOptions {
+  once: boolean;
+}
+interface AbortSignalEventTarget {
+  addEventListener: (name: 'abort', listener: () => void, options?: AbortSignalEventTargetAddOptions) => void;
+  removeEventListener: (name: 'abort', listener: () => void) => void;
+  aborted?: boolean;
+}
+interface AbortSignalEventEmitter {
+  off: (name: 'abort', listener: () => void) => void;
+  once: (name: 'abort', listener: () => void) => void;
+}
+type AbortSignalAny = AbortSignalEventTarget | AbortSignalEventEmitter;
+type ResourceLimits = Worker extends {
+  resourceLimits?: infer T;
+} ? T : object;
+interface Options {
+  filename?: string | null;
+  runtime?: 'worker_threads' | 'child_process';
+  name?: string;
+  minThreads?: number;
+  maxThreads?: number;
+  idleTimeout?: number;
+  terminateTimeout?: number;
+  maxQueue?: number | 'auto';
+  concurrentTasksPerWorker?: number;
+  useAtomics?: boolean;
+  resourceLimits?: ResourceLimits;
+  maxMemoryLimitBeforeRecycle?: number;
+  argv?: string[];
+  execArgv?: string[];
+  env?: Record<string, string>;
+  workerData?: any;
+  taskQueue?: TaskQueue;
+  trackUnmanagedFds?: boolean;
+  isolateWorkers?: boolean;
+  teardown?: string;
+}
+interface FilledOptions extends Options {
+  filename: string | null;
+  name: string;
+  runtime: NonNullable<Options['runtime']>;
+  minThreads: number;
+  maxThreads: number;
+  idleTimeout: number;
+  maxQueue: number;
+  concurrentTasksPerWorker: number;
+  useAtomics: boolean;
+  taskQueue: TaskQueue;
+}
+interface RunOptions {
+  transferList?: TransferList;
+  channel?: TinypoolChannel;
+  filename?: string | null;
+  signal?: AbortSignalAny | null;
+  name?: string | null;
+  runtime?: Options['runtime'];
+}
+type TransferList = MessagePort extends {
+  postMessage(value: any, transferList: infer T): any;
+} ? T : never;
+type TransferListItem$1 = TransferList extends (infer T)[] ? T : never;
+declare class Tinypool extends EventEmitterAsyncResource {
+  #private;
+  constructor(options?: Options);
+  run(task: any, options?: RunOptions): Promise<any>;
+  destroy(): Promise<void>;
+  get options(): FilledOptions;
+  get threads(): TinypoolWorker[];
+  get queueSize(): number;
+  cancelPendingTasks(): void;
+  recycleWorkers(options?: Pick<Options, 'runtime'>): Promise<void>;
+  get completed(): number;
+  get duration(): number;
+  static get isWorkerThread(): boolean;
+  static get workerData(): any;
+  static get version(): string;
+  static move(val: Transferable | TransferListItem$1 | ArrayBufferView | ArrayBuffer | MessagePort): MessagePort | ArrayBuffer | Transferable | ArrayBufferView;
+  static get transferableSymbol(): symbol;
+  static get valueSymbol(): symbol;
+  static get queueOptionsSymbol(): symbol;
+}
+declare const _workerId: number;
+
+//#endregion
+export { Options, ReadyMessage, RequestMessage, ResponseMessage, StartupMessage, Task, TaskQueue, Tinypool, TinypoolChannel, TinypoolData, TinypoolPrivateData, TinypoolWorker, TinypoolWorkerMessage, Transferable, Tinypool as default, isMovable, isTaskQueue, isTransferable, kFieldCount, kQueueOptions, kRequestCountField, kResponseCountField, kTransferable, kValue, markMovable, _workerId as workerId };