"Portable test batches for hosted CI sharding"

Every once query test-plan --format json export is portable and replayable. Fresh CI workers can execute assigned opaque batches with once test --plan plan.json --batch <id> without transferring private discovery caches or reconstructing runner filters. Matching checkouts and tool versions can live at different paths. Changed discovery inputs or configuration fail validation; file fixtures and exact-result checks remain intact.

Portable execution returns all assigned batch outcomes, including failed tests, with explicit completeness and success fields. External coordinators can attach a test-run group and partition index to authenticated native diagnostics and submit one consolidated test report per CI partition without duplicating each batch's cases.