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-core/utils/pluginUtils.d.ts

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+import { WorkboxPlugin } from '../types.js';
+import '../_version.js';
+export declare const pluginUtils: {
+    filter: (plugins: WorkboxPlugin[], callbackName: string) => WorkboxPlugin[];
+};

pwa/node_modules/workbox-core/utils/pluginUtils.js

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+/*
+  Copyright 2018 Google LLC
+
+  Use of this source code is governed by an MIT-style
+  license that can be found in the LICENSE file or at
+  https://opensource.org/licenses/MIT.
+*/
+import '../_version.js';
+export const pluginUtils = {
+    filter: (plugins, callbackName) => {
+        return plugins.filter((plugin) => callbackName in plugin);
+    },
+};

pwa/node_modules/workbox-core/utils/pluginUtils.mjs

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+export * from './pluginUtils.js';

pwa/node_modules/workbox-core/utils/welcome.d.ts

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+import '../_version.js';

pwa/node_modules/workbox-core/utils/welcome.js

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+/*
+  Copyright 2019 Google LLC
+
+  Use of this source code is governed by an MIT-style
+  license that can be found in the LICENSE file or at
+  https://opensource.org/licenses/MIT.
+*/
+import { logger } from '../_private/logger.js';
+import '../_version.js';
+// A WorkboxCore instance must be exported before we can use the logger.
+// This is so it can get the current log level.
+if (process.env.NODE_ENV !== 'production') {
+    const padding = '   ';
+    logger.groupCollapsed('Welcome to Workbox!');
+    logger.log(`You are currently using a development build. ` +
+        `By default this will switch to prod builds when not on localhost. ` +
+        `You can force this with workbox.setConfig({debug: true|false}).`);
+    logger.log(`📖 Read the guides and documentation\n` +
+        `${padding}https://developers.google.com/web/tools/workbox/`);
+    logger.log(`❓ Use the [workbox] tag on Stack Overflow to ask questions\n` +
+        `${padding}https://stackoverflow.com/questions/ask?tags=workbox`);
+    logger.log(`🐛 Found a bug? Report it on GitHub\n` +
+        `${padding}https://github.com/GoogleChrome/workbox/issues/new`);
+    logger.groupEnd();
+}

pwa/node_modules/workbox-core/utils/welcome.mjs

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+export * from './welcome.js';