Fix DataTables column configuration error on pay page

Fixed "Requested unknown parameter '1' for row 0, column 1" error
by adding explicit column definitions to the DataTable initialization.

The issue occurred because DataTables was initialized without column
definitions, but data was being added as arrays. DataTables needs
explicit column configuration to properly map array data to columns.

Changes:
- Added "columns" configuration to DataTable initialization
- Defined all 4 columns with proper titles
- Set "orderable: false" for Actions column

This fixes the popup error that appeared when visiting /users/1/pay

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

app/views/pay/index.html.erb

@@ -207,7 +207,13 @@ function createDataTable(){
       },
       "autoWidth": false,
       "searching": true,
-      "ordering": true
+      "ordering": true,
+      "columns": [
+        { "title": "Account Number" },
+        { "title": "Routing Number" },
+        { "title": "Deposit %" },
+        { "title": "Actions", "orderable": false }
+      ]
     });
 };