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/why-is-node-running/README.md

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+# why-is-node-running
+
+Node is running but you don't know why? `why-is-node-running` is here to help you.
+
+## Installation
+
+Node 8 and above:
+
+```bash
+npm i why-is-node-running -g
+```
+
+Earlier Node versions (no longer supported):
+
+```bash
+npm i why-is-node-running@v1.x -g
+```
+
+## Usage
+
+```js
+const log = require('why-is-node-running') // should be your first require
+const net = require('net')
+
+function createServer () {
+  const server = net.createServer()
+  setInterval(function () {}, 1000)
+  server.listen(0)
+}
+
+createServer()
+createServer()
+
+setTimeout(function () {
+  log() // logs out active handles that are keeping node running
+}, 100)
+```
+
+Save the file as `example.js`, then execute:
+
+```bash
+node ./example.js
+```
+
+Here's the output:
+
+```
+There are 5 handle(s) keeping the process running
+
+# Timeout
+/home/maf/dev/node_modules/why-is-node-running/example.js:6  - setInterval(function () {}, 1000)
+/home/maf/dev/node_modules/why-is-node-running/example.js:10 - createServer()
+
+# TCPSERVERWRAP
+/home/maf/dev/node_modules/why-is-node-running/example.js:7  - server.listen(0)
+/home/maf/dev/node_modules/why-is-node-running/example.js:10 - createServer()
+
+# Timeout
+/home/maf/dev/node_modules/why-is-node-running/example.js:6  - setInterval(function () {}, 1000)
+/home/maf/dev/node_modules/why-is-node-running/example.js:11 - createServer()
+
+# TCPSERVERWRAP
+/home/maf/dev/node_modules/why-is-node-running/example.js:7  - server.listen(0)
+/home/maf/dev/node_modules/why-is-node-running/example.js:11 - createServer()
+
+# Timeout
+/home/maf/dev/node_modules/why-is-node-running/example.js:13 - setTimeout(function () {
+```
+
+**Important Note!**
+`unref`ed timers do not prevent the Node process from exiting. If you are running with Node v11.0.0 and above, `unref`ed timers will not be listed in the above list. Unfortunately, this is not supported in node versions below v11.0.0.
+
+## CLI
+
+You can also run `why-is-node-running` as a standalone if you don't want to include it inside your code. Sending `SIGUSR1`/`SIGINFO` signal to the process will produce the log. (`Ctrl + T` on macOS and BSD systems)
+
+```bash
+why-is-node-running /path/to/some/file.js
+```
+
+```
+probing module /path/to/some/file.js
+kill -SIGUSR1 31115 for logging
+```
+
+To trigger the log:
+
+```
+kill -SIGUSR1 31115
+```
+
+## Require CLI Option
+
+You can also use the node `-r` option to include `why-is-node-running`:
+
+```bash
+node -r why-is-node-running/include /path/to/some/file.js
+```
+
+The steps are otherwise the same as the above CLI section
+
+## License
+
+MIT