Add baseline unit tests and fix home server normalization

lib/src/handlers/auth_handlers.dart

@@ -397,10 +397,14 @@ String? normalizeHomeServer(String homeServerOrHost) {
     return null;
   }
 
-  return uri
-      .replace(path: '', query: null, fragment: null)
-      .toString()
-      .replaceAll(RegExp(r'/$'), '');
+  final normalized = Uri(
+    scheme: uri.scheme,
+    userInfo: uri.userInfo,
+    host: uri.host,
+    port: uri.hasPort ? uri.port : null,
+  ).toString();
+
+  return normalized.replaceAll(RegExp(r'/$'), '');
 }
 
 String defaultSchemeForHost(String host) {