Add the id-based reconcile tests to ReplaceProgramScheduleItemsReconcileTests:
reorder moves state with the logical item (the non-vacuous core — proven to fail
under forced-positional), insert-in-middle, delete-unreferenced, unknown-id→422,
duplicate-id→422, and stale-version+unknown-id→412 (412 precedes 422, §7c). The
GET→map→PUT lossless round-trip now round-trips r.Id so it exercises id-mode.
Threads the new int? Id through all command/wire construction sites in tests.
Docs: api-conventions §7c (stable child identity + the deliberate #2-#5 positional
asymmetry) and a decisions.md entry.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>