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/pathe/dist/utils.cjs

@@ -0,0 +1,58 @@
+'use strict';
+
+const index = require('./shared/pathe.1f0a373c.cjs');
+
+const pathSeparators = /* @__PURE__ */ new Set(["/", "\\", void 0]);
+const normalizedAliasSymbol = Symbol.for("pathe:normalizedAlias");
+function normalizeAliases(_aliases) {
+  if (_aliases[normalizedAliasSymbol]) {
+    return _aliases;
+  }
+  const aliases = Object.fromEntries(
+    Object.entries(_aliases).sort(([a], [b]) => _compareAliases(a, b))
+  );
+  for (const key in aliases) {
+    for (const alias in aliases) {
+      if (alias === key || key.startsWith(alias)) {
+        continue;
+      }
+      if (aliases[key].startsWith(alias) && pathSeparators.has(aliases[key][alias.length])) {
+        aliases[key] = aliases[alias] + aliases[key].slice(alias.length);
+      }
+    }
+  }
+  Object.defineProperty(aliases, normalizedAliasSymbol, {
+    value: true,
+    enumerable: false
+  });
+  return aliases;
+}
+function resolveAlias(path, aliases) {
+  const _path = index.normalizeWindowsPath(path);
+  aliases = normalizeAliases(aliases);
+  for (const [alias, to] of Object.entries(aliases)) {
+    if (!_path.startsWith(alias)) {
+      continue;
+    }
+    const _alias = hasTrailingSlash(alias) ? alias.slice(0, -1) : alias;
+    if (hasTrailingSlash(_path[_alias.length])) {
+      return index.join(to, _path.slice(alias.length));
+    }
+  }
+  return _path;
+}
+const FILENAME_RE = /(^|[/\\])([^/\\]+?)(?=(\.[^.]+)?$)/;
+function filename(path) {
+  return path.match(FILENAME_RE)?.[2];
+}
+function _compareAliases(a, b) {
+  return b.split("/").length - a.split("/").length;
+}
+function hasTrailingSlash(path = "/") {
+  const lastChar = path[path.length - 1];
+  return lastChar === "/" || lastChar === "\\";
+}
+
+exports.filename = filename;
+exports.normalizeAliases = normalizeAliases;
+exports.resolveAlias = resolveAlias;