Replace drag-and-drop image preview tests (broken in CI per #8143) with
execution-based widget value assertions using the partial_execution
workflow. Tests the same changeTracker snapshot/restore path through
PreviewAny widget values, which work reliably in CI.
Image preview drag-drop doesn't reliably sync in CI, matching the
same known issue documented in imagePreview.spec.ts. Mark all 3
E2E tests as test.fixme until #8143 is resolved.
- Add unit tests for snapshotOutputs/restoreOutputs round-trip
- Add unit test verifying snapshotOutputs returns deep clone
- Add unit test for resetAllOutputsAndPreviews clearing all state
- Add unit tests for restoreOutputs + execution interaction
- Add unit tests for merge mode with input previews
- Add unit tests for setNodeOutputs widget path edge cases
- Add E2E tests for LoadImage preview surviving tab switch
- Add E2E test for preview surviving execution + tab switch
- Add E2E test for independent preview preservation across tabs