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/lib/vocabularies/applicator/anyOf.ts

@@ -0,0 +1,14 @@
+import type {CodeKeywordDefinition, ErrorNoParams, AnySchema} from "../../types"
+import {validateUnion} from "../code"
+
+export type AnyOfError = ErrorNoParams<"anyOf", AnySchema[]>
+
+const def: CodeKeywordDefinition = {
+  keyword: "anyOf",
+  schemaType: "array",
+  trackErrors: true,
+  code: validateUnion,
+  error: {message: "must match a schema in anyOf"},
+}
+
+export default def