* test: shared switch-on fixtures so 71 layout-owner test files run with the switch on
- layoutApplyTestTransport answers layout.apply (accept, apply to main's model with its frame, pending, refuse)
- main's loaded layout as snapshot frames, shared from the frame-sync test
- tab-layout maps for the editor store harnesses; missing store methods in the main harnesses
- workspaceRepos/registerWorkspaceRepos so main's load keeps seeded layouts
- ORCA_LAYOUT_OWNER=main runs vitest with the switch on
- the 4 rollback-build tests stay switch-off, labelled
* test: keep switch-off assertions exact, settle only after layout commands, reset the transport per test
* test: parse the transport's command without Reflect.get; name the staged-session type
* test: pin the test transport in the layout.apply census; route the autosave fixture as unit support
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Co-authored-by: E2E Test <e2e@test.local>
Jinwoo HongandE2E Test
4e998861e1