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/jsonpointer/LICENSE.md

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+The MIT License (MIT)
+
+Copyright (c) 2011-2015 Jan Lehnardt <jan@apache.org> & Marc Bachmann <https://github.com/marcbachmann> 
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.

pwa/node_modules/jsonpointer/README.md

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+# JSON Pointer for Node.js
+
+This is an implementation of [JSON Pointer](https://tools.ietf.org/html/rfc6901).
+
+## CLI
+
+Looking to filter JSON from the command line? Check out [jsonpointer-cli](https://github.com/joeyespo/jsonpointer-cli).
+
+## Usage
+```javascript
+var jsonpointer = require('jsonpointer');
+var obj = { foo: 1, bar: { baz: 2}, qux: [3, 4, 5]};
+
+jsonpointer.get(obj, '/foo');     // returns 1
+jsonpointer.get(obj, '/bar/baz'); // returns 2
+jsonpointer.get(obj, '/qux/0');   // returns 3
+jsonpointer.get(obj, '/qux/1');   // returns 4
+jsonpointer.get(obj, '/qux/2');   // returns 5
+jsonpointer.get(obj, '/quo');     // returns undefined
+
+jsonpointer.set(obj, '/foo', 6);  // sets obj.foo = 6;
+jsonpointer.set(obj, '/qux/-', 6) // sets obj.qux = [3, 4, 5, 6]
+
+var pointer = jsonpointer.compile('/foo')
+pointer.get(obj)    // returns 1
+pointer.set(obj, 1) // sets obj.foo = 1
+```
+
+## Testing
+
+    $ npm test
+    All tests pass.
+    $
+
+[![Node.js CI](https://github.com/janl/node-jsonpointer/actions/workflows/node.js.yml/badge.svg)](https://github.com/janl/node-jsonpointer/actions/workflows/node.js.yml)
+
+## Author
+
+(c) 2011-2021 Jan Lehnardt <jan@apache.org> & Marc Bachmann <https://github.com/marcbachmann>
+
+Thanks to all contributors.
+
+## License
+
+MIT License.

pwa/node_modules/jsonpointer/jsonpointer.d.ts

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+interface JSONPointer {
+    /**
+     * Looks up a JSON pointer in an object
+     */
+    get(object: Object): any;
+
+
+    /**
+     * Set a value for a JSON pointer on object
+     */
+    set(object: Object, value: any): void;
+}
+
+
+declare namespace JSONPointer {
+    /**
+     * Looks up a JSON pointer in an object
+     */
+    function get(object: Object, pointer: string): any;
+
+
+    /**
+     * Set a value for a JSON pointer on object
+     */
+    function set(object: Object, pointer: string, value: any): void;
+
+
+    /**
+     *  Builds a JSONPointer instance from a pointer value.
+     */
+    function compile(pointer: string): JSONPointer;
+}
+
+
+export = JSONPointer;

pwa/node_modules/jsonpointer/jsonpointer.js

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+var hasExcape = /~/
+var escapeMatcher = /~[01]/g
+function escapeReplacer (m) {
+  switch (m) {
+    case '~1': return '/'
+    case '~0': return '~'
+  }
+  throw new Error('Invalid tilde escape: ' + m)
+}
+
+function untilde (str) {
+  if (!hasExcape.test(str)) return str
+  return str.replace(escapeMatcher, escapeReplacer)
+}
+
+function setter (obj, pointer, value) {
+  var part
+  var hasNextPart
+
+  for (var p = 1, len = pointer.length; p < len;) {
+    if (pointer[p] === 'constructor' || pointer[p] === 'prototype' || pointer[p] === '__proto__') return obj
+
+    part = untilde(pointer[p++])
+    hasNextPart = len > p
+
+    if (typeof obj[part] === 'undefined') {
+      // support setting of /-
+      if (Array.isArray(obj) && part === '-') {
+        part = obj.length
+      }
+
+      // support nested objects/array when setting values
+      if (hasNextPart) {
+        if ((pointer[p] !== '' && pointer[p] < Infinity) || pointer[p] === '-') obj[part] = []
+        else obj[part] = {}
+      }
+    }
+
+    if (!hasNextPart) break
+    obj = obj[part]
+  }
+
+  var oldValue = obj[part]
+  if (value === undefined) delete obj[part]
+  else obj[part] = value
+  return oldValue
+}
+
+function compilePointer (pointer) {
+  if (typeof pointer === 'string') {
+    pointer = pointer.split('/')
+    if (pointer[0] === '') return pointer
+    throw new Error('Invalid JSON pointer.')
+  } else if (Array.isArray(pointer)) {
+    for (const part of pointer) {
+      if (typeof part !== 'string' && typeof part !== 'number') {
+        throw new Error('Invalid JSON pointer. Must be of type string or number.')
+      }
+    }
+    return pointer
+  }
+
+  throw new Error('Invalid JSON pointer.')
+}
+
+function get (obj, pointer) {
+  if (typeof obj !== 'object') throw new Error('Invalid input object.')
+  pointer = compilePointer(pointer)
+  var len = pointer.length
+  if (len === 1) return obj
+
+  for (var p = 1; p < len;) {
+    obj = obj[untilde(pointer[p++])]
+    if (len === p) return obj
+    if (typeof obj !== 'object' || obj === null) return undefined
+  }
+}
+
+function set (obj, pointer, value) {
+  if (typeof obj !== 'object') throw new Error('Invalid input object.')
+  pointer = compilePointer(pointer)
+  if (pointer.length === 0) throw new Error('Invalid JSON pointer for set.')
+  return setter(obj, pointer, value)
+}
+
+function compile (pointer) {
+  var compiled = compilePointer(pointer)
+  return {
+    get: function (object) {
+      return get(object, compiled)
+    },
+    set: function (object, value) {
+      return set(object, compiled, value)
+    }
+  }
+}
+
+exports.get = get
+exports.set = set
+exports.compile = compile

pwa/node_modules/jsonpointer/package.json

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+{
+  "name": "jsonpointer",
+  "description": "Simple JSON Addressing.",
+  "tags": [
+    "util",
+    "simple",
+    "util",
+    "utility"
+  ],
+  "version": "5.0.1",
+  "author": "Jan Lehnardt <jan@apache.org>",
+  "contributors": [
+    "Joe Hildebrand <joe-github@cursive.net>",
+    "Marc Bachmann <marc.brookman@gmail.com>"
+  ],
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/janl/node-jsonpointer.git"
+  },
+  "bugs": {
+    "url": "http://github.com/janl/node-jsonpointer/issues"
+  },
+  "engines": {
+    "node": ">=0.10.0"
+  },
+  "main": "./jsonpointer",
+  "typings": "jsonpointer.d.ts",
+  "files": [
+    "jsonpointer.js",
+    "jsonpointer.d.ts"
+  ],
+  "scripts": {
+    "test": "npm run test:standard && npm run test:all",
+    "test:standard": "standard",
+    "test:all": "node test.js",
+    "semantic-release": "semantic-release pre && npm publish && semantic-release post"
+  },
+  "license": "MIT",
+  "devDependencies": {
+    "semantic-release": "^18.0.0",
+    "standard": "^16.0.4"
+  },
+  "standard": {
+    "ignore": [
+      "test.js"
+    ]
+  }
+}