Fix UI issues in Dashboard and Student screens

frontend/lib/ui/screens/dashboard/dashboard_screen.dart

@@ -688,7 +688,7 @@ class _DashboardScreenState extends ConsumerState<DashboardScreen> {
           crossAxisCount: crossAxisCount,
           crossAxisSpacing: 16,
           mainAxisSpacing: 16,
-          mainAxisExtent: isSquare ? 115 : 85,
+          mainAxisExtent: isSquare ? 135 : 85,
         ),
         children: [
           StatCard(

frontend/lib/ui/screens/students/students_screen.dart

@@ -82,6 +82,7 @@ class _StudentsScreenState extends ConsumerState<StudentsScreen> {
           final currentQuery = ref.read(studentQueryProvider).search;
           if (_searchController.text != currentQuery) {
             _searchController.text = currentQuery;
+            if (mounted) setState(() {});
           }
         }
       });
@@ -254,28 +255,7 @@ class _StudentsScreenState extends ConsumerState<StudentsScreen> {
     );
   }
 
-  Widget _batchActionBtn({
-    required IconData icon,
-    required String label,
-    required Color color,
-    required VoidCallback onTap,
-  }) {
-    return InkWell(
-      onTap: onTap,
-      borderRadius: BorderRadius.circular(8),
-      child: Padding(
-        padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 6),
-        child: Column(
-          mainAxisSize: MainAxisSize.min,
-          children: [
-            Icon(icon, color: color, size: 22),
-            const SizedBox(height: 4),
-            Text(label, style: TextStyle(color: color, fontSize: 11, fontWeight: FontWeight.bold)),
-          ],
-        ),
-      ),
-    );
-  }
+
 
   void _showBulkEnrollModal() {
     showDialog(

frontend/lib/ui/shared/inputs/app_search_bar.dart

@@ -73,7 +73,12 @@ class _AppSearchBarState extends ConsumerState<AppSearchBar> {
 
   void _onTextChanged() {
     final hasText = _controller.text.isNotEmpty;
-    if (hasText != _hasText) setState(() => _hasText = hasText);
+    if (hasText != _hasText) {
+      setState(() {
+        _hasText = hasText;
+        if (hasText) _isExpanded = true;
+      });
+    }
     
     // Update overlay if history is visible
     if (_overlayEntry != null && widget.enableHistory) {
@@ -273,9 +278,8 @@ class _AppSearchBarState extends ConsumerState<AppSearchBar> {
                       widget.onSubmitted?.call('');
                       setState(() {
                         _hasText = false;
-                        _isExpanded = true;
                       });
-                      _focusNode.requestFocus();
+                      _focusNode.unfocus();
                     },
                   )
                 : null,