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/2020/OrdinaryDefineOwnProperty.js

@@ -0,0 +1,54 @@
+'use strict';
+
+var $gOPD = require('gopd');
+var $SyntaxError = require('es-errors/syntax');
+var $TypeError = require('es-errors/type');
+var isObject = require('es-object-atoms/isObject');
+
+var isPropertyDescriptor = require('../helpers/records/property-descriptor');
+
+var IsAccessorDescriptor = require('./IsAccessorDescriptor');
+var IsExtensible = require('./IsExtensible');
+var isPropertyKey = require('../helpers/isPropertyKey');
+var ToPropertyDescriptor = require('./ToPropertyDescriptor');
+var SameValue = require('./SameValue');
+var ValidateAndApplyPropertyDescriptor = require('./ValidateAndApplyPropertyDescriptor');
+
+// https://262.ecma-international.org/6.0/#sec-ordinarydefineownproperty
+
+module.exports = function OrdinaryDefineOwnProperty(O, P, Desc) {
+	if (!isObject(O)) {
+		throw new $TypeError('Assertion failed: O must be an Object');
+	}
+	if (!isPropertyKey(P)) {
+		throw new $TypeError('Assertion failed: P must be a Property Key');
+	}
+	if (!isPropertyDescriptor(Desc)) {
+		throw new $TypeError('Assertion failed: Desc must be a Property Descriptor');
+	}
+	if (!$gOPD) {
+		// ES3/IE 8 fallback
+		if (IsAccessorDescriptor(Desc)) {
+			throw new $SyntaxError('This environment does not support accessor property descriptors.');
+		}
+		var creatingNormalDataProperty = !(P in O)
+			&& Desc['[[Writable]]']
+			&& Desc['[[Enumerable]]']
+			&& Desc['[[Configurable]]']
+			&& '[[Value]]' in Desc;
+		var settingExistingDataProperty = (P in O)
+			&& (!('[[Configurable]]' in Desc) || Desc['[[Configurable]]'])
+			&& (!('[[Enumerable]]' in Desc) || Desc['[[Enumerable]]'])
+			&& (!('[[Writable]]' in Desc) || Desc['[[Writable]]'])
+			&& '[[Value]]' in Desc;
+		if (creatingNormalDataProperty || settingExistingDataProperty) {
+			O[P] = Desc['[[Value]]']; // eslint-disable-line no-param-reassign
+			return SameValue(O[P], Desc['[[Value]]']);
+		}
+		throw new $SyntaxError('This environment does not support defining non-writable, non-enumerable, or non-configurable properties');
+	}
+	var desc = $gOPD(O, P);
+	var current = desc && ToPropertyDescriptor(desc);
+	var extensible = IsExtensible(O);
+	return ValidateAndApplyPropertyDescriptor(O, P, extensible, Desc, current);
+};