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/randombytes/.travis.yml

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+sudo: false
+language: node_js
+matrix:
+  include:
+    - node_js: '7'
+      env: TEST_SUITE=test
+    - node_js: '6'
+      env: TEST_SUITE=test
+    - node_js: '5'
+      env: TEST_SUITE=test
+    - node_js: '4'
+      env: TEST_SUITE=test
+    - node_js: '4'
+      env: TEST_SUITE=phantom
+script: "npm run-script $TEST_SUITE"

pwa/node_modules/randombytes/.zuul.yml

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+ui: tape

pwa/node_modules/randombytes/LICENSE

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+MIT License
+
+Copyright (c) 2017 crypto-browserify
+
+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/randombytes/README.md

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+randombytes
+===
+
+[![Version](http://img.shields.io/npm/v/randombytes.svg)](https://www.npmjs.org/package/randombytes) [![Build Status](https://travis-ci.org/crypto-browserify/randombytes.svg?branch=master)](https://travis-ci.org/crypto-browserify/randombytes)
+
+randombytes from node that works in the browser.  In node you just get crypto.randomBytes, but in the browser it uses .crypto/msCrypto.getRandomValues
+
+```js
+var randomBytes = require('randombytes');
+randomBytes(16);//get 16 random bytes
+randomBytes(16, function (err, resp) {
+  // resp is 16 random bytes
+});
+```

pwa/node_modules/randombytes/browser.js

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+'use strict'
+
+// limit of Crypto.getRandomValues()
+// https://developer.mozilla.org/en-US/docs/Web/API/Crypto/getRandomValues
+var MAX_BYTES = 65536
+
+// Node supports requesting up to this number of bytes
+// https://github.com/nodejs/node/blob/master/lib/internal/crypto/random.js#L48
+var MAX_UINT32 = 4294967295
+
+function oldBrowser () {
+  throw new Error('Secure random number generation is not supported by this browser.\nUse Chrome, Firefox or Internet Explorer 11')
+}
+
+var Buffer = require('safe-buffer').Buffer
+var crypto = global.crypto || global.msCrypto
+
+if (crypto && crypto.getRandomValues) {
+  module.exports = randomBytes
+} else {
+  module.exports = oldBrowser
+}
+
+function randomBytes (size, cb) {
+  // phantomjs needs to throw
+  if (size > MAX_UINT32) throw new RangeError('requested too many random bytes')
+
+  var bytes = Buffer.allocUnsafe(size)
+
+  if (size > 0) {  // getRandomValues fails on IE if size == 0
+    if (size > MAX_BYTES) { // this is the max bytes crypto.getRandomValues
+      // can do at once see https://developer.mozilla.org/en-US/docs/Web/API/window.crypto.getRandomValues
+      for (var generated = 0; generated < size; generated += MAX_BYTES) {
+        // buffer.slice automatically checks if the end is past the end of
+        // the buffer so we don't have to here
+        crypto.getRandomValues(bytes.slice(generated, generated + MAX_BYTES))
+      }
+    } else {
+      crypto.getRandomValues(bytes)
+    }
+  }
+
+  if (typeof cb === 'function') {
+    return process.nextTick(function () {
+      cb(null, bytes)
+    })
+  }
+
+  return bytes
+}

pwa/node_modules/randombytes/index.js

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+module.exports = require('crypto').randomBytes

pwa/node_modules/randombytes/package.json

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+{
+  "name": "randombytes",
+  "version": "2.1.0",
+  "description": "random bytes from browserify stand alone",
+  "main": "index.js",
+  "scripts": {
+    "test": "standard && node test.js | tspec",
+    "phantom": "zuul --phantom -- test.js",
+    "local": "zuul --local --no-coverage -- test.js"
+  },
+  "repository": {
+    "type": "git",
+    "url": "git@github.com:crypto-browserify/randombytes.git"
+  },
+  "keywords": [
+    "crypto",
+    "random"
+  ],
+  "author": "",
+  "license": "MIT",
+  "bugs": {
+    "url": "https://github.com/crypto-browserify/randombytes/issues"
+  },
+  "homepage": "https://github.com/crypto-browserify/randombytes",
+  "browser": "browser.js",
+  "devDependencies": {
+    "phantomjs": "^1.9.9",
+    "standard": "^10.0.2",
+    "tap-spec": "^2.1.2",
+    "tape": "^4.6.3",
+    "zuul": "^3.7.2"
+  },
+  "dependencies": {
+    "safe-buffer": "^5.1.0"
+  }
+}

pwa/node_modules/randombytes/test.js

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+var test = require('tape')
+var randomBytes = require('./')
+var MAX_BYTES = 65536
+var MAX_UINT32 = 4294967295
+
+test('sync', function (t) {
+  t.plan(9)
+  t.equals(randomBytes(0).length, 0, 'len: ' + 0)
+  t.equals(randomBytes(3).length, 3, 'len: ' + 3)
+  t.equals(randomBytes(30).length, 30, 'len: ' + 30)
+  t.equals(randomBytes(300).length, 300, 'len: ' + 300)
+  t.equals(randomBytes(17 + MAX_BYTES).length, 17 + MAX_BYTES, 'len: ' + 17 + MAX_BYTES)
+  t.equals(randomBytes(MAX_BYTES * 100).length, MAX_BYTES * 100, 'len: ' + MAX_BYTES * 100)
+  t.throws(function () {
+    randomBytes(MAX_UINT32 + 1)
+  })
+  t.throws(function () {
+    t.equals(randomBytes(-1))
+  })
+  t.throws(function () {
+    t.equals(randomBytes('hello'))
+  })
+})
+
+test('async', function (t) {
+  t.plan(9)
+
+  randomBytes(0, function (err, resp) {
+    if (err) throw err
+
+    t.equals(resp.length, 0, 'len: ' + 0)
+  })
+
+  randomBytes(3, function (err, resp) {
+    if (err) throw err
+
+    t.equals(resp.length, 3, 'len: ' + 3)
+  })
+
+  randomBytes(30, function (err, resp) {
+    if (err) throw err
+
+    t.equals(resp.length, 30, 'len: ' + 30)
+  })
+
+  randomBytes(300, function (err, resp) {
+    if (err) throw err
+
+    t.equals(resp.length, 300, 'len: ' + 300)
+  })
+
+  randomBytes(17 + MAX_BYTES, function (err, resp) {
+    if (err) throw err
+
+    t.equals(resp.length, 17 + MAX_BYTES, 'len: ' + 17 + MAX_BYTES)
+  })
+
+  randomBytes(MAX_BYTES * 100, function (err, resp) {
+    if (err) throw err
+
+    t.equals(resp.length, MAX_BYTES * 100, 'len: ' + MAX_BYTES * 100)
+  })
+
+  t.throws(function () {
+    randomBytes(MAX_UINT32 + 1, function () {
+      t.ok(false, 'should not get here')
+    })
+  })
+
+  t.throws(function () {
+    randomBytes(-1, function () {
+      t.ok(false, 'should not get here')
+    })
+  })
+
+  t.throws(function () {
+    randomBytes('hello', function () {
+      t.ok(false, 'should not get here')
+    })
+  })
+})