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/README.md

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+[npm]: https://img.shields.io/npm/v/@rollup/plugin-replace
+[npm-url]: https://www.npmjs.com/package/@rollup/plugin-replace
+[size]: https://packagephobia.now.sh/badge?p=@rollup/plugin-replace
+[size-url]: https://packagephobia.now.sh/result?p=@rollup/plugin-replace
+
+[![npm][npm]][npm-url]
+[![size][size]][size-url]
+[![libera manifesto](https://img.shields.io/badge/libera-manifesto-lightgrey.svg)](https://liberamanifesto.com)
+
+# @rollup/plugin-replace
+
+🍣 A Rollup plugin which replaces targeted strings in files while bundling.
+
+## Requirements
+
+This plugin requires an [LTS](https://github.com/nodejs/Release) Node version (v8.0.0+) and Rollup v1.20.0+.
+
+## Install
+
+Using npm:
+
+```console
+npm install @rollup/plugin-replace --save-dev
+```
+
+## Usage
+
+Create a `rollup.config.js` [configuration file](https://www.rollupjs.org/guide/en/#configuration-files) and import the plugin:
+
+```js
+import replace from '@rollup/plugin-replace';
+
+export default {
+  input: 'src/index.js',
+  output: {
+    dir: 'output',
+    format: 'cjs'
+  },
+  plugins: [
+    replace({
+      'process.env.NODE_ENV': JSON.stringify('production'),
+      __buildDate__: () => JSON.stringify(new Date()),
+      __buildVersion: 15
+    })
+  ]
+};
+```
+
+Then call `rollup` either via the [CLI](https://www.rollupjs.org/guide/en/#command-line-reference) or the [API](https://www.rollupjs.org/guide/en/#javascript-api).
+
+The configuration above will replace every instance of `process.env.NODE_ENV` with `"production"` and `__buildDate__` with the result of the given function in any file included in the build.
+
+_Note: Values must be either primitives (e.g. string, number) or `function` that returns a string. For complex values, use `JSON.stringify`. To replace a target with a value that will be evaluated as a string, set the value to a quoted string (e.g. `"test"`) or use `JSON.stringify` to preprocess the target string safely._
+
+Typically, `@rollup/plugin-replace` should be placed in `plugins` _before_ other plugins so that they may apply optimizations, such as dead code removal.
+
+## Options
+
+In addition to the properties and values specified for replacement, users may also specify the options below.
+
+### `delimiters`
+
+Type: `Array[...String, String]`<br>
+Default: `['\b', '\b']`
+
+Specifies the boundaries around which strings will be replaced. By default, delimiters are [word boundaries](https://www.regular-expressions.info/wordboundaries.html). See [Word Boundaries](#word-boundaries) below for more information.
+
+### `preventAssignment`
+
+Type: `Boolean`<br>
+Default: `false`
+
+Prevents replacing strings where they are followed by a single equals sign. For example, where the plugin is called as follows:
+
+```js
+replace({
+  values: {
+    'process.env.DEBUG': 'false'
+  }
+});
+```
+
+Observe the following code:
+
+```js
+// Input
+process.env.DEBUG = false;
+if (process.env.DEBUG == true) {
+  //
+}
+// Without `preventAssignment`
+false = false; // this throws an error because false cannot be assigned to
+if (false == true) {
+  //
+}
+// With `preventAssignment`
+process.env.DEBUG = false;
+if (false == true) {
+  //
+}
+```
+
+### `exclude`
+
+Type: `String` | `Array[...String]`<br>
+Default: `null`
+
+A [minimatch pattern](https://github.com/isaacs/minimatch), or array of patterns, which specifies the files in the build the plugin should _ignore_. By default no files are ignored.
+
+### `include`
+
+Type: `String` | `Array[...String]`<br>
+Default: `null`
+
+A [minimatch pattern](https://github.com/isaacs/minimatch), or array of patterns, which specifies the files in the build the plugin should operate on. By default all files are targeted.
+
+### `values`
+
+Type: `{ [key: String]: Replacement }`, where `Replacement` is either a string or a `function` that returns a string.
+Default: `{}`
+
+To avoid mixing replacement strings with the other options, you can specify replacements in the `values` option. For example, the following signature:
+
+```js
+replace({
+  include: ['src/**/*.js'],
+  changed: 'replaced'
+});
+```
+
+Can be replaced with:
+
+```js
+replace({
+  include: ['src/**/*.js'],
+  values: {
+    changed: 'replaced'
+  }
+});
+```
+
+## Word Boundaries
+
+By default, values will only match if they are surrounded by _word boundaries_.
+
+Consider the following options and build file:
+
+```js
+module.exports = {
+  ...
+  plugins: [replace({ changed: 'replaced' })]
+};
+```
+
+```js
+// file.js
+console.log('changed');
+console.log('unchanged');
+```
+
+The result would be:
+
+```js
+// file.js
+console.log('replaced');
+console.log('unchanged');
+```
+
+To ignore word boundaries and replace every instance of the string, wherever it may be, specify empty strings as delimiters:
+
+```js
+export default {
+  ...
+  plugins: [
+    replace({
+      changed: 'replaced',
+      delimiters: ['', '']
+    })
+  ]
+};
+```
+
+## Meta
+
+[CONTRIBUTING](/.github/CONTRIBUTING.md)
+
+[LICENSE (MIT)](/LICENSE)