implemented comprehensive accessibility (A11y) support across the app

lib/widget/app_progress_indicator.dart

@@ -1,24 +1,43 @@
 import 'package:flutter/material.dart';
 
+import 'a11y/a11y_labels.dart';
+
 class AppProgressIndicator extends StatelessWidget {
   final double size;
   final double strokeWidth;
   final Color? color;
+  final String semanticsLabel;
 
   const AppProgressIndicator._({
     required this.size,
     required this.strokeWidth,
     this.color,
+    this.semanticsLabel = A11yLabels.loading,
   });
 
-  const AppProgressIndicator.small({Color? color})
-    : this._(size: 16, strokeWidth: 2, color: color);
+  const AppProgressIndicator.small({Color? color, String? semanticsLabel})
+    : this._(
+        size: 16,
+        strokeWidth: 2,
+        color: color,
+        semanticsLabel: semanticsLabel ?? A11yLabels.loading,
+      );
 
-  const AppProgressIndicator.medium({Color? color})
-    : this._(size: 24, strokeWidth: 2.5, color: color);
+  const AppProgressIndicator.medium({Color? color, String? semanticsLabel})
+    : this._(
+        size: 24,
+        strokeWidth: 2.5,
+        color: color,
+        semanticsLabel: semanticsLabel ?? A11yLabels.loading,
+      );
 
-  const AppProgressIndicator.large({Color? color})
-    : this._(size: 40, strokeWidth: 3, color: color);
+  const AppProgressIndicator.large({Color? color, String? semanticsLabel})
+    : this._(
+        size: 40,
+        strokeWidth: 3,
+        color: color,
+        semanticsLabel: semanticsLabel ?? A11yLabels.loading,
+      );
 
   @override
   Widget build(BuildContext context) {
@@ -29,6 +48,7 @@ class AppProgressIndicator extends StatelessWidget {
       child: CircularProgressIndicator(
         strokeWidth: strokeWidth,
         valueColor: AlwaysStoppedAnimation<Color>(resolved),
+        semanticsLabel: semanticsLabel,
       ),
     );
   }