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/@babel/helper-optimise-call-expression/lib/index.js

@@ -0,0 +1,33 @@
+"use strict";
+
+Object.defineProperty(exports, "__esModule", {
+  value: true
+});
+exports.default = optimiseCallExpression;
+var _t = require("@babel/types");
+const {
+  callExpression,
+  identifier,
+  isIdentifier,
+  isSpreadElement,
+  memberExpression,
+  optionalCallExpression,
+  optionalMemberExpression
+} = _t;
+function optimiseCallExpression(callee, thisNode, args, optional) {
+  if (args.length === 1 && isSpreadElement(args[0]) && isIdentifier(args[0].argument, {
+    name: "arguments"
+  })) {
+    if (optional) {
+      return optionalCallExpression(optionalMemberExpression(callee, identifier("apply"), false, true), [thisNode, args[0].argument], false);
+    }
+    return callExpression(memberExpression(callee, identifier("apply")), [thisNode, args[0].argument]);
+  } else {
+    if (optional) {
+      return optionalCallExpression(optionalMemberExpression(callee, identifier("call"), false, true), [thisNode, ...args], false);
+    }
+    return callExpression(memberExpression(callee, identifier("call")), [thisNode, ...args]);
+  }
+}
+
+//# sourceMappingURL=index.js.map