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/es-abstract/2024/IsViewOutOfBounds.js

@@ -0,0 +1,48 @@
+'use strict';
+
+var $TypeError = require('es-errors/type');
+
+var IsDetachedBuffer = require('./IsDetachedBuffer');
+var IsFixedLengthArrayBuffer = require('./IsFixedLengthArrayBuffer');
+
+var isDataViewWithBufferWitnessRecord = require('../helpers/records/data-view-with-buffer-witness-record');
+
+var dataViewBuffer = require('data-view-buffer');
+var dataViewByteLength = require('data-view-byte-length');
+var dataViewByteOffset = require('data-view-byte-offset');
+
+// https://262.ecma-international.org/15.0/#sec-isviewoutofbounds
+
+module.exports = function IsViewOutOfBounds(viewRecord) {
+	if (!isDataViewWithBufferWitnessRecord(viewRecord)) {
+		throw new $TypeError('Assertion failed: `viewRecord` must be a DataView With Buffer Witness Record');
+	}
+
+	var view = viewRecord['[[Object]]']; // step 1
+
+	var bufferByteLength = viewRecord['[[CachedBufferByteLength]]']; // step 2
+
+	if (IsDetachedBuffer(dataViewBuffer(view)) !== (bufferByteLength === 'DETACHED')) {
+		// step 3
+		throw new $TypeError('Assertion failed: `IsDetachedBuffer(dataViewBuffer(view))` must be true if and only if `bufferByteLength === ~DETACHED~');
+	}
+
+	if (bufferByteLength === 'DETACHED') {
+		return true; // step 4
+	}
+
+	var byteOffsetStart = dataViewByteOffset(view); // step 5
+
+	var isFixed = IsFixedLengthArrayBuffer(dataViewBuffer(view));
+
+	var viewByteLength = isFixed ? dataViewByteLength(view) : 'AUTO'; // view.[[ByteLength]]
+	var byteOffsetEnd = viewByteLength === 'AUTO' ? bufferByteLength : byteOffsetStart + viewByteLength; // steps 6 - 7
+
+	if (byteOffsetStart > bufferByteLength || byteOffsetEnd > bufferByteLength) {
+		return true; // step 8
+	}
+
+	// 9. NOTE: 0-length DataViews are not considered out-of-bounds.
+
+	return false; // step 10
+};