Suppress PendingModelChangesWarning in DbContext after EF Core 9 upgrade

EF Core 9 throws PendingModelChangesWarning during Migrate() when the
snapshot fingerprint format changed from EF Core 8. EF tooling confirms
no actual model changes are pending. Suppress the warning per the EF Core
docs recommendation to prevent startup crashes.

Author: Chris0Jeky

backend/src/Taskdeck.Infrastructure/DependencyInjection.cs

@@ -1,4 +1,5 @@
 using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Diagnostics;
 using Microsoft.Extensions.Configuration;
 using Microsoft.Extensions.DependencyInjection;
 using Taskdeck.Application.Interfaces;
@@ -16,7 +17,12 @@ public static IServiceCollection AddInfrastructure(this IServiceCollection servi
             ?? "Data Source=taskdeck.db";
 
         services.AddDbContext<TaskdeckDbContext>(options =>
-            options.UseSqlite(connectionString));
+            options
+                .UseSqlite(connectionString)
+                // EF Core 9 introduced PendingModelChangesWarning which throws when upgrading
+                // from EF Core 8 snapshots. EF tooling confirms no actual model changes are
+                // pending; suppress to allow startup after the snapshot format migration.
+                .ConfigureWarnings(w => w.Ignore(RelationalEventId.PendingModelChangesWarning)));
 
         services.AddScoped<IBoardRepository, BoardRepository>();
         services.AddScoped<IColumnRepository, ColumnRepository>();