Minor language-specific case tweaks (#2396)

lib/pages/app.dart

@@ -232,7 +232,10 @@ class _AppPageState extends State<AppPage> {
                         : const EdgeInsetsDirectional.fromSTEB(0, 6, 0, 6),
                     margin: const EdgeInsetsDirectional.fromSTEB(0, 6, 0, 0),
                     child: Text(
-                      tr('downloadX', args: [tr('releaseAsset').toLowerCase()]),
+                      tr(
+                        'downloadX',
+                        args: [lowerCaseIfEnglish(tr('releaseAsset'))],
+                      ),
                       textAlign: TextAlign.center,
                       style: Theme.of(context).textTheme.labelSmall!.copyWith(
                         decoration: TextDecoration.underline,

lib/pages/apps.dart

@@ -1072,7 +1072,10 @@ class AppsPageState extends State<AppsPage> {
                       Navigator.of(context).pop();
                     },
                     child: Text(
-                      tr('downloadX', args: [tr('releaseAsset').toLowerCase()]),
+                      tr(
+                        'downloadX',
+                        args: [lowerCaseIfEnglish(tr('releaseAsset'))],
+                      ),
                     ),
                   ),
                   const Divider(),

lib/pages/import_export.dart

@@ -545,7 +545,7 @@ class _ImportExportPageState extends State<ImportExportPage> {
                                 child: Text(
                                   tr(
                                     'searchX',
-                                    args: [tr('source').toLowerCase()],
+                                    args: [lowerCaseIfEnglish(tr('source'))],
                                   ),
                                 ),
                               ),