Fix backend↔database mismatches found verifying against Fuchs_Database

Verified every [dbo].[...] object the backend calls against the SSDT project.
Two real mismatches fixed (both would fail at runtime):

- Banking search (bam/btl mode=s) called a non-existent
  [dbo].[fds__getBankingtransactions_list2] and dropped @tgtdate. The actual
  proc (and the legacy call) is [dbo].[fds__getBankingtransfers_list2]
  (@tgtdate,@mode,@search,@authuser) — corrected name + parameters.
- Widget generic branch called a phantom [dbo].[fds__getWidget] that never
  existed (legacy only had my/one; the dashboard only requests wdg/my, wdg/one).
  The default branch now returns 404 instead of hitting a missing proc.

(The 'fuchs__admin_logdebug' reference is only in a commented-out line.)

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Fuchs/Services/FuchsWidgetService.cs

@@ -97,19 +97,15 @@ public class FuchsWidgetService : IWidgetService
         return await BuildWidgetResponse(userAccountId, dbSec, shortName, wdg);
     }
 
-    // ── Generic widget by id ──────────────────────────────────────────────────
-    private async Task<IActionResult> HandleWidgetGeneric(string widgetId, string userAccountId,
+    // ── Unknown widget id ──────────────────────────────────────────────────────
+    // The dashboard only requests "my" and "one"; there is no generic widget
+    // source in the schema (the legacy code had no such procedure either).
+    private Task<IActionResult> HandleWidgetGeneric(string widgetId, string userAccountId,
         DatabaseSecurity dbSec)
     {
-        var pl   = Params(userAccountId, SQL_VarChar("@widget", widgetId, dbNull_IfEmpty: true));
-        var dset = await getSQLDataSet_async(
-            "EXECUTE [dbo].[fds__getWidget] @widget, @authuser;",
-            Conn, pl, tablenames: new[] { "admin", "data" }, Security: dbSec);
-        return await JSONAsync(new
-        {
-            admin = dset.Table("admin").FirstRow.toObjectDictionary(),
-            data  = dset.Tables("data").toArrayofObjectDictionaries()
-        });
+        _ = dbSec;
+        _logger.LogWarning("GetWidgetAsync: unknown widget id '{WidgetId}' requested by user={User}", widgetId, userAccountId);
+        return Task.FromResult<IActionResult>(new NotFoundResult());
     }
 
     // ── Widget renderer dispatcher ────────────────────────────────────────────