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/@apideck/better-ajv-errors/README.md

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+[![npm (scoped)](https://img.shields.io/npm/v/@apideck/better-ajv-errors?color=brightgreen)](https://npmjs.com/@apideck/better-ajv-errors) [![npm](https://img.shields.io/npm/dm/@apideck/better-ajv-errors)](https://npmjs.com/@apideck/better-ajv-errors) [![GitHub Workflow Status](https://img.shields.io/github/workflow/status/apideck-libraries/better-ajv-errors/CI)](https://github.com/apideck-libraries/better-ajv-errors/actions/workflows/main.yml?query=branch%3Amain++)
+
+# @apideck/better-ajv-errors 👮‍♀️
+
+> Human-friendly JSON Schema validation for APIs
+
+
+- Readable and helpful [ajv](https://github.com/ajv-validator/ajv) errors
+- API-friendly format
+- Suggestions for spelling mistakes
+- Minimal footprint: 1.56 kB (gzip + minified)
+
+![better-ajv-errors output Example](https://user-images.githubusercontent.com/8850410/118274790-e0529e80-b4c5-11eb-8188-9097c8064c61.png)
+
+## Install
+
+```bash
+$ yarn add @apideck/better-ajv-errors
+```
+
+or
+
+```bash
+$ npm i @apideck/better-ajv-errors
+```
+
+Also make sure that you've installed [ajv](https://www.npmjs.com/package/ajv) at version 8 or higher.
+
+## Usage
+
+After validating some data with ajv, pass the errors to `betterAjvErrors`
+
+```ts
+import Ajv from 'ajv';
+import { betterAjvErrors } from '@apideck/better-ajv-errors';
+
+// Without allErrors: true, ajv will only return the first error
+const ajv = new Ajv({ allErrors: true });
+
+const valid = ajv.validate(schema, data);
+
+if (!valid) {
+  const betterErrors = betterAjvErrors({ schema, data, errors: ajv.errors });
+}
+```
+
+## API
+
+### betterAjvErrors
+
+Function that formats ajv validation errors in a human-friendly format.
+
+#### Parameters
+
+- `options: BetterAjvErrorsOptions`
+  - `errors: ErrorObject[] | null | undefined` Your ajv errors, you will find these in the `errors` property of your ajv instance (`ErrorObject` is a type from the ajv package).
+  - `data: Object` The data you passed to ajv to be validated.
+  - `schema: JSONSchema` The schema you passed to ajv to validate against.
+  - `basePath?: string` An optional base path to prefix paths returned by `betterAjvErrors`. For example, in APIs, it could be useful to use `'{requestBody}'` or `'{queryParemeters}'` as a basePath. This will make it clear to users where exactly the error occurred.
+
+#### Return Value
+
+- `ValidationError[]` Array of formatted errors (properties of `ValidationError` below)
+  - `message: string` Formatted error message
+  - `suggestion?: string` Optional suggestion based on provided data and schema
+  - `path: string` Object path where the error occurred (example: `.foo.bar.0.quz`)
+  - `context: { errorType: DefinedError['keyword']; [additionalContext: string]: unknown }` `errorType` is `error.keyword` proxied from `ajv`. `errorType` can be used as a key for i18n if needed. There might be additional properties on context, based on the type of error.
+
+## Related
+
+- [atlassian/better-ajv-errors](https://github.com/atlassian/better-ajv-errors) was the inspiration for this library. Atlassian's library is more focused on CLI errors, this library is focused on developer-friendly API error messages.