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/object-inspect/test/has.js

@@ -0,0 +1,15 @@
+'use strict';
+
+var inspect = require('../');
+var test = require('tape');
+var mockProperty = require('mock-property');
+
+test('when Object#hasOwnProperty is deleted', function (t) {
+    t.plan(1);
+    var arr = [1, , 3]; // eslint-disable-line no-sparse-arrays
+
+    t.teardown(mockProperty(Array.prototype, 1, { value: 2 })); // this is needed to account for "in" vs "hasOwnProperty"
+    t.teardown(mockProperty(Object.prototype, 'hasOwnProperty', { 'delete': true }));
+
+    t.equal(inspect(arr), '[ 1, , 3 ]');
+});