[CI] (.github/workflows, docs/ci, tools/trace_replay): drop retrace-split's repeated inproc rows

- with build-linux reused, retrace-split runs its spawn rows plus OpenRA's inproc rows (the wire evidence); the other 75 inproc rows are replayed by the retrace job's inproc-acceptance rows on the same library
- trace_cases.py: github-split-matrix takes --transports and --keep-inproc; the self-test proves the spawn rows unchanged and every dropped inproc row an inproc-acceptance row; only a narrowed matrix that comes out empty raises, so the workflow's named error for an empty full subset still prints
- trace-cases: the spawn-only subset is only a saving, so a failed self-test or an empty result is a warning, the output is not written and retrace-split takes the full subset
- run_trace_case.cmake: MGTRACE_EXPECT_IPC (a harness name) requires the client's IPC line to carry the listed tokens; retrace-split legs prove strict=0 role-split-state=1 run-ahead=1 and a changed default reds every leg with the rows to restore; the acceptance rows prove strict=1 role-split-state=1 run-ahead=1 and gain the refusal census; canned tests in test_run_trace_case.py

docs/ci/ci-cleanup-log.md

@@ -52,6 +52,7 @@ them wrong.
 | 2026-10-17 | the integration-gpu entries that pin their own `MOBILEGL_TRANSPORT` (804 inproc, 1446 spawn, 131 monolith) and the 12 `TcpServer` fixture entries only they need, in the inproc-acceptance leg (both passes) | Test / `integration` (inproc-acceptance) | their pin overrides the only variable the two legs differ in, so they ran identically in both (173 paired runs; the one one-sided red was a port bind fixed by cde6512b) | the monolith-control leg, which runs them on every branch; `transport_pinned.py` proves per run that the trimmed selection lost exactly that population (else the leg runs everything) and that the monolith-control leg ran every one; skip census: the monolith-control lanes list their own names and the inproc-acceptance lanes drop the pinned ones |
 | 2026-10-17 | `Strict split lane` on the disaggregation branches (dev keeps it) | Test / `integration-split-strict` | with the role-split state defaulting on, its environment equals the dual-block census lane's, whose entries are a superset (31 paired runs after the flip, never red only in the strict lane) | the dual-block step's first run leaves the knob at its default, proves per entry from its client log that strict, the dual block and run-ahead resolved on (`ipc-config`), writes the integration-split part of its JUnit as `strict-split.xml` (every name exactly once, `junit_tally.py --select-from`), and makes the strict lane's checks on it (hard green, two-sided marker census, StrictArming ran); a default that changed reruns the census with the knob set |
 | 2026-10-17 | `Magma split lane (strict, dual-block)` on the disaggregation branches when the dual-block step proved its defaults | Test / `integration-split-strict` | the dual-block census run covers the `integration-magma-split` label in the same environment | the dual-block census run |
+| 2026-10-17 | the 75 retrace-split inproc rows other than OpenRA's, when `build-linux-split` reuses `build-linux` | Test / `retrace-split` | the retrace job's inproc-acceptance rows replay the same cases on the same library, strict and with the dual block and run-ahead on; no one-sided pair since 10-05 | the inproc-acceptance rows, which now prove per leg from the client log that they run with strict=1, role-split-state=1 and run-ahead=1 (`MGTRACE_EXPECT_IPC`) and keep a refusal census; every remaining retrace-split leg proves its defaults (strict=0, role-split-state=1, run-ahead=1) and a changed default reds every leg with the rows to restore; `trace_cases.py --self-test-split-matrix` (disaggregation branches) proves every dropped row is an acceptance row; OpenRA's inproc rows stay for the wire evidence |
 
 ## Kept after investigation