Add loading states to MudDataGrid components

Implemented loading indicators and progress colors for all MudDataGrid instances across Events, Students, Teams, and Registration components to enhance user experience during data loading operations.

WebApp/Components/Features/Events/Index.razor

@@ -22,7 +22,9 @@
                  RowsPerPage="50"
                  Dense="true"
                  Striped="true"
-                 Hover="true">
+                 Hover="true"
+                 Loading="@_isLoading"
+                 LoadingProgressColor="Color.Primary">
         <Columns>
             <PropertyColumn Property="@(e => e.Name)" Title="Event Name" Sortable="true">
                 <CellTemplate>
@@ -71,20 +73,28 @@
 
 @code {
     MudDataGrid<EventDefinition> _dataGrid = null!;
+    private bool _isLoading = true;
 
     private async Task<GridData<EventDefinition>> ServerReload(GridState<EventDefinition> state)
     {
-
-        var query = Context.Events.OrderBy(e => e.Name).Where(state.FilterDefinitions).OrderBy(state.SortDefinitions);
-
-        var totalItems = await query.CountAsync();
-        var pagedData = await query.Skip(state.Page * state.PageSize).Take(state.PageSize).ToArrayAsync();
-
-        return new GridData<EventDefinition>
+        _isLoading = true;
+        try
         {
-            TotalItems = totalItems,
-            Items = pagedData
-        };
+            var query = Context.Events.OrderBy(e => e.Name).Where(state.FilterDefinitions).OrderBy(state.SortDefinitions);
+
+            var totalItems = await query.CountAsync();
+            var pagedData = await query.Skip(state.Page * state.PageSize).Take(state.PageSize).ToArrayAsync();
+
+            return new GridData<EventDefinition>
+            {
+                TotalItems = totalItems,
+                Items = pagedData
+            };
+        }
+        finally
+        {
+            _isLoading = false;
+        }
     }
 
     private async Task DeleteEventDefinition(EventDefinition evt)