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/deep-eql/package.json

@@ -0,0 +1,73 @@
+{
+  "name": "deep-eql",
+  "version": "5.0.2",
+  "description": "Improved deep equality testing for Node.js and the browser.",
+  "keywords": [
+    "chai util",
+    "deep equal",
+    "object equal",
+    "testing"
+  ],
+  "repository": {
+    "type": "git",
+    "url": "git@github.com:chaijs/deep-eql.git"
+  },
+  "license": "MIT",
+  "author": "Jake Luer <jake@alogicalparadox.com>",
+  "contributors": [
+    "Keith Cirkel (https://github.com/keithamus)",
+    "dougluce (https://github.com/dougluce)",
+    "Lorenz Leutgeb (https://github.com/flowlo)"
+  ],
+  "type": "module",
+  "main": "./index.js",
+  "files": [
+    "index.js",
+    "deep-eql.js"
+  ],
+  "scripts": {
+    "bench": "node bench",
+    "lint": "eslint --ignore-path .gitignore .",
+    "semantic-release": "semantic-release pre && semantic-release post",
+    "pretest": "npm run lint",
+    "test": "npm run test:node && npm run test:browser",
+    "test:browser": "web-test-runner",
+    "test:node": "istanbul cover _mocha",
+    "upload-coverage": "lcov-result-merger 'coverage/**/lcov.info' | coveralls; exit 0",
+    "watch": "web-test-runner --watch"
+  },
+  "eslintConfig": {
+    "extends": [
+      "strict/es5"
+    ],
+    "rules": {
+      "complexity": 0,
+      "no-underscore-dangle": 0,
+      "no-use-before-define": 0,
+      "spaced-comment": 0
+    },
+    "parserOptions": {
+      "sourceType": "module",
+      "ecmaVersion": 2015
+    }
+  },
+  "devDependencies": {
+    "@js-temporal/polyfill": "^0.4.3",
+    "@rollup/plugin-commonjs": "^24.1.0",
+    "@web/test-runner": "^0.16.1",
+    "benchmark": "^2.1.0",
+    "coveralls": "^3.1.1",
+    "eslint": "^7.32.0",
+    "eslint-config-strict": "^14.0.1",
+    "eslint-plugin-filenames": "^1.3.2",
+    "istanbul": "^0.4.2",
+    "kewlr": "^0.4.1",
+    "lcov-result-merger": "^1.0.2",
+    "lodash.isequal": "^4.4.0",
+    "mocha": "^9.1.1",
+    "simple-assert": "^2.0.0"
+  },
+  "engines": {
+    "node": ">=6"
+  }
+}