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/jake/README.md

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+### Jake -- the JavaScript build tool for Node.js
+
+[![Build Status](https://travis-ci.org/jakejs/jake.svg?branch=master)](https://travis-ci.org/jakejs/jake)
+
+Documentation site at [http://jakejs.com](http://jakejs.com/)
+
+### Contributing
+1. [Install node](http://nodejs.org/#download).
+2. Clone this repository `$ git clone git@github.com:jakejs/jake.git`.
+3. Install dependencies `$ npm install`.
+4. Run tests with `$ npm test`.
+5. Start Hacking!
+
+### License
+
+Licensed under the Apache License, Version 2.0
+(<http://www.apache.org/licenses/LICENSE-2.0>)