feat: add Plaid transaction handling and async queue processing

- introduced new migration to add Cursor column to AccountMetadata.
- updated AppDbContext model snapshot to reflect changes in the database schema.
- implemented async queue processing with ChannelAsyncQueue and AsyncQueueHostedService.
- created Plaid transaction handlers for added, modified, and removed transactions.
- developed PlaidTransactionService and PlaidTransactionSyncer for syncing transactions.
- added SyncUpdatesProcessor to handle sync updates from Plaid.
- updated tests to accommodate changes in institution and account metadata handling.

src/FiscalOS.Infra/Transactions/Plaid/PlaidRemovedTransactionHandler.cs

@@ -0,0 +1,33 @@
+namespace FiscalOS.Infra.Transactions.Plaid;
+
+internal interface IPlaidRemovedTransactionHandler
+{
+  Task HandleAsync(IEnumerable<RemovedTransaction> removed, CancellationToken cancellationToken);
+}
+
+internal sealed class PlaidRemovedTransactionHandler : IPlaidRemovedTransactionHandler
+{
+  private readonly AppDbContext _appDbContext;
+
+  private PlaidRemovedTransactionHandler(AppDbContext appDbContext)
+  {
+    _appDbContext = appDbContext;
+  }
+
+  public static PlaidRemovedTransactionHandler From(IServiceProvider serviceProvider)
+  {
+    return new(
+      serviceProvider.GetRequiredService<AppDbContext>()
+    );
+  }
+
+  public async Task HandleAsync(IEnumerable<RemovedTransaction> removed, CancellationToken cancellationToken)
+  {
+    var removedIdsList = removed.Select(t => t.TransactionId);
+
+    await _appDbContext.Transactions
+      .Where(t => t.Metadata is PlaidTransactionMetadata && removedIdsList.Contains(((PlaidTransactionMetadata)t.Metadata).PlaidId))
+      .ExecuteDeleteAsync(cancellationToken)
+      .ConfigureAwait(false);
+  }
+}