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.API/Institutions/GetAvailable/Endpoint.cs

@@ -13,7 +13,7 @@ internal static class Endpoint
     HttpContext httpContext,
     [FromRoute] Guid id,
     [FromServices] AppDbContext appDbContext,
-    [FromServices] PlaidService plaidService,
+    [FromServices] IPlaidAccountService plaidAccountService,
     [FromServices] IEncryptor encryptor,
     CancellationToken ct
   )
@@ -37,13 +37,13 @@ internal static class Endpoint
 
     var institution = user.Institutions.First();
 
-    if (institution.Metadata is not PlaidMetadata plaidMetadata)
+    if (institution.Metadata is not PlaidInstitutionMetadata plaidMetadata)
     {
       return Results.BadRequest();
     }
 
     var accessToken = await encryptor.DecryptAsyncFor(user, plaidMetadata.EncryptedAccessToken, ct);
-    var accounts = await plaidService.GetAccountsAsync(accessToken);
+    var accounts = await plaidAccountService.GetAccountsAsync(accessToken);
     var accountsDtos = accounts.Select(a => AvailableAccountDto.From(plaidMetadata, a));
 
     return Results.Ok(Response.From(accountsDtos));