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/ajv/dist/vocabularies/draft2020.js

@@ -0,0 +1,23 @@
+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
+const core_1 = require("./core");
+const validation_1 = require("./validation");
+const applicator_1 = require("./applicator");
+const dynamic_1 = require("./dynamic");
+const next_1 = require("./next");
+const unevaluated_1 = require("./unevaluated");
+const format_1 = require("./format");
+const metadata_1 = require("./metadata");
+const draft2020Vocabularies = [
+    dynamic_1.default,
+    core_1.default,
+    validation_1.default,
+    (0, applicator_1.default)(true),
+    format_1.default,
+    metadata_1.metadataVocabulary,
+    metadata_1.contentVocabulary,
+    next_1.default,
+    unevaluated_1.default,
+];
+exports.default = draft2020Vocabularies;
+//# sourceMappingURL=draft2020.js.map