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/lodash/_createCaseFirst.js

@@ -0,0 +1,33 @@
+var castSlice = require('./_castSlice'),
+    hasUnicode = require('./_hasUnicode'),
+    stringToArray = require('./_stringToArray'),
+    toString = require('./toString');
+
+/**
+ * Creates a function like `_.lowerFirst`.
+ *
+ * @private
+ * @param {string} methodName The name of the `String` case method to use.
+ * @returns {Function} Returns the new case function.
+ */
+function createCaseFirst(methodName) {
+  return function(string) {
+    string = toString(string);
+
+    var strSymbols = hasUnicode(string)
+      ? stringToArray(string)
+      : undefined;
+
+    var chr = strSymbols
+      ? strSymbols[0]
+      : string.charAt(0);
+
+    var trailing = strSymbols
+      ? castSlice(strSymbols, 1).join('')
+      : string.slice(1);
+
+    return chr[methodName]() + trailing;
+  };
+}
+
+module.exports = createCaseFirst;