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/2021/RawBytesToNumeric.js

@@ -0,0 +1,67 @@
+'use strict';
+
+var GetIntrinsic = require('get-intrinsic');
+var callBound = require('call-bound');
+
+var $RangeError = require('es-errors/range');
+var $SyntaxError = require('es-errors/syntax');
+var $TypeError = require('es-errors/type');
+var $BigInt = GetIntrinsic('%BigInt%', true);
+
+var hasOwnProperty = require('./HasOwnProperty');
+var IsArray = require('./IsArray');
+var IsBigIntElementType = require('./IsBigIntElementType');
+var IsUnsignedElementType = require('./IsUnsignedElementType');
+
+var bytesAsFloat32 = require('../helpers/bytesAsFloat32');
+var bytesAsFloat64 = require('../helpers/bytesAsFloat64');
+var bytesAsInteger = require('../helpers/bytesAsInteger');
+var every = require('../helpers/every');
+var isByteValue = require('../helpers/isByteValue');
+
+var $reverse = callBound('Array.prototype.reverse');
+var $slice = callBound('Array.prototype.slice');
+
+var tableTAO = require('./tables/typed-array-objects');
+
+// https://262.ecma-international.org/11.0/#sec-rawbytestonumeric
+
+module.exports = function RawBytesToNumeric(type, rawBytes, isLittleEndian) {
+	if (typeof type !== 'string' || !hasOwnProperty(tableTAO.size, '$' + type)) {
+		throw new $TypeError('Assertion failed: `type` must be a TypedArray element type');
+	}
+	if (!IsArray(rawBytes) || !every(rawBytes, isByteValue)) {
+		throw new $TypeError('Assertion failed: `rawBytes` must be an Array of bytes');
+	}
+	if (typeof isLittleEndian !== 'boolean') {
+		throw new $TypeError('Assertion failed: `isLittleEndian` must be a Boolean');
+	}
+
+	var elementSize = tableTAO.size['$' + type]; // step 1
+
+	if (rawBytes.length !== elementSize) {
+		// this assertion is not in the spec, but it'd be an editorial error if it were ever violated
+		throw new $RangeError('Assertion failed: `rawBytes` must have a length of ' + elementSize + ' for type ' + type);
+	}
+
+	var isBigInt = IsBigIntElementType(type);
+	if (isBigInt && !$BigInt) {
+		throw new $SyntaxError('this environment does not support BigInts');
+	}
+
+	// eslint-disable-next-line no-param-reassign
+	rawBytes = $slice(rawBytes, 0, elementSize);
+	if (!isLittleEndian) {
+		$reverse(rawBytes); // step 2
+	}
+
+	if (type === 'Float32') { // step 3
+		return bytesAsFloat32(rawBytes);
+	}
+
+	if (type === 'Float64') { // step 4
+		return bytesAsFloat64(rawBytes);
+	}
+
+	return bytesAsInteger(rawBytes, elementSize, IsUnsignedElementType(type), isBigInt);
+};