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/errors.ts

@@ -0,0 +1,18 @@
+import type {TypeError} from "../compile/validate/dataType"
+import type {ApplicatorKeywordError} from "./applicator"
+import type {ValidationKeywordError} from "./validation"
+import type {FormatError} from "./format/format"
+import type {UnevaluatedPropertiesError} from "./unevaluated/unevaluatedProperties"
+import type {UnevaluatedItemsError} from "./unevaluated/unevaluatedItems"
+import type {DependentRequiredError} from "./validation/dependentRequired"
+import type {DiscriminatorError} from "./discriminator"
+
+export type DefinedError =
+  | TypeError
+  | ApplicatorKeywordError
+  | ValidationKeywordError
+  | FormatError
+  | UnevaluatedPropertiesError
+  | UnevaluatedItemsError
+  | DependentRequiredError
+  | DiscriminatorError