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/@rollup/plugin-replace/package.json

@@ -0,0 +1,73 @@
+{
+  "name": "@rollup/plugin-replace",
+  "version": "2.4.2",
+  "publishConfig": {
+    "access": "public"
+  },
+  "description": "Replace strings in files while bundling",
+  "license": "MIT",
+  "repository": "rollup/plugins",
+  "author": "Rich Harris <richard.a.harris@gmail.com>",
+  "homepage": "https://github.com/rollup/plugins/tree/master/packages/replace#readme",
+  "bugs": "https://github.com/rollup/plugins/issues",
+  "main": "dist/rollup-plugin-replace.cjs.js",
+  "module": "dist/rollup-plugin-replace.es.js",
+  "scripts": {
+    "build": "rollup -c",
+    "ci:coverage": "nyc pnpm run test && nyc report --reporter=text-lcov > coverage.lcov",
+    "ci:lint": "pnpm run build && pnpm run lint",
+    "ci:lint:commits": "commitlint --from=${CIRCLE_BRANCH} --to=${CIRCLE_SHA1}",
+    "ci:test": "pnpm run test -- --verbose && pnpm run test:ts",
+    "lint": "pnpm run lint:js && pnpm run lint:docs && pnpm run lint:package",
+    "lint:docs": "prettier --single-quote --arrow-parens avoid --trailing-comma none --write README.md",
+    "lint:js": "eslint --fix --cache src test types --ext .js,.ts",
+    "lint:package": "prettier --write package.json --plugin=prettier-plugin-package",
+    "prebuild": "del-cli dist",
+    "prepare": "pnpm run build",
+    "prepublishOnly": "pnpm run lint && pnpm run test",
+    "pretest": "pnpm run build",
+    "test": "ava",
+    "test:ts": "tsc types/index.d.ts test/types.ts --noEmit"
+  },
+  "files": [
+    "dist",
+    "src",
+    "types",
+    "README.md"
+  ],
+  "keywords": [
+    "rollup",
+    "plugin",
+    "replace",
+    "es2015",
+    "npm",
+    "modules"
+  ],
+  "peerDependencies": {
+    "rollup": "^1.20.0 || ^2.0.0"
+  },
+  "dependencies": {
+    "@rollup/pluginutils": "^3.1.0",
+    "magic-string": "^0.25.7"
+  },
+  "devDependencies": {
+    "@rollup/plugin-buble": "^0.21.3",
+    "del-cli": "^3.0.1",
+    "locate-character": "^2.0.5",
+    "rollup": "^2.23.0",
+    "source-map": "^0.7.3",
+    "typescript": "^3.9.7"
+  },
+  "types": "types/index.d.ts",
+  "ava": {
+    "babel": {
+      "compileEnhancements": false
+    },
+    "files": [
+      "!**/fixtures/**",
+      "!**/helpers/**",
+      "!**/recipes/**",
+      "!**/types.ts"
+    ]
+  }
+}