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/tsx/dist/patch-repl.cjs

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+"use strict";var i=Object.defineProperty;var a=(r,t)=>i(r,"name",{value:t,configurable:!0});var n=require("node:repl"),u=require("esbuild");const f=a(r=>{const{eval:t}=r,c=a(async function(e,l,s,o){try{e=(await u.transform(e,{sourcefile:s,loader:"ts",tsconfigRaw:{compilerOptions:{preserveValueImports:!0}},define:{require:"global.require"}})).code}catch{}return t.call(this,e,l,s,o)},"preEval");r.eval=c},"patchEval"),{start:p}=n;n.start=function(){const r=Reflect.apply(p,this,arguments);return f(r),r};