test(12.2-05): cover every Go behaviour of phase 12.2

- lagoon: Date and TimeOfDay through JSON, text and real DATE/TIME
  columns; Fill text fallback without changing earlier conversions;
  required on zero dates; deferred_bindings shape, store isolation and
  envelope; PurgeDeferred cut-off, after-commit blobs, SKIP LOCKED,
  skipped types and the deferred:purge command
- attach: Store limits, extensions, MIME patterns, default lists, key
  shape and blob cleanup; IsAllowedImage formats, polyglots, ceiling
- conga and pact: framework purge schedule entry and forged jobs; the
  six relation child hook interfaces
- cabana: fileupload and datepicker compile, upload, remove, caption,
  reorder and bounds; deferred commit order, rollback, applied-only and
  concurrent saves; relation contracts, forms, CRUD, deferral, schema

modules/cabana/testdata/deferred/models/gadget/fields.yaml

@@ -30,6 +30,7 @@ fields:
         type: fileupload
         mode: image
         maxFiles: 3
+        maxFilesize: 0.5
     manual:
         label: Manual
         type: fileupload