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/terser/main.js

@@ -0,0 +1,27 @@
+import "./lib/transform.js";
+import "./lib/mozilla-ast.js";
+import { minify } from "./lib/minify.js";
+
+export { minify, minify_sync } from "./lib/minify.js";
+export { run_cli as _run_cli } from "./lib/cli.js";
+
+export async function _default_options() {
+    const defs = {};
+
+    Object.keys(infer_options({ 0: 0 })).forEach((component) => {
+        const options = infer_options({
+            [component]: {0: 0}
+        });
+
+        if (options) defs[component] = options;
+    });
+    return defs;
+}
+
+async function infer_options(options) {
+    try {
+        await minify("", options);
+    } catch (error) {
+        return error.defs;
+    }
+}