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/path-parse/README.md

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+# path-parse [![Build Status](https://travis-ci.org/jbgutierrez/path-parse.svg?branch=master)](https://travis-ci.org/jbgutierrez/path-parse)
+
+> Node.js [`path.parse(pathString)`](https://nodejs.org/api/path.html#path_path_parse_pathstring) [ponyfill](https://ponyfill.com).
+
+## Install
+
+```
+$ npm install --save path-parse
+```
+
+## Usage
+
+```js
+var pathParse = require('path-parse');
+
+pathParse('/home/user/dir/file.txt');
+//=> {
+//       root : "/",
+//       dir : "/home/user/dir",
+//       base : "file.txt",
+//       ext : ".txt",
+//       name : "file"
+//   }
+```
+
+## API
+
+See [`path.parse(pathString)`](https://nodejs.org/api/path.html#path_path_parse_pathstring) docs.
+
+### pathParse(path)
+
+### pathParse.posix(path)
+
+The Posix specific version.
+
+### pathParse.win32(path)
+
+The Windows specific version.
+
+## License
+
+MIT © [Javier Blanco](http://jbgutierrez.info)