[CI, Tools] (...): replay trace cases in shards from one fixture cache

docs/ci/ci-cleanup-log.md

@@ -64,6 +64,10 @@ them wrong.
 | 2026-10-18 | `Negative control A (corrupted snapshot)` and `Keep lane logs before controls` | Test / `integration-verify-split` | the first re-ran the ten `VerifySplit.ClearThenReadPixelsScenario` entries of both backends with the same knob and accepted any red; the second only kept the lane's logs from being overwritten by that rerun | the in-lane `VerifySplitCorrupted` and `VerifySplitReadCorrupted` entries of both backends, required by name (`Verify-split control entries`); that the ambient entries arm is the per-entry arm proof, and that they run fatal is `VerifySplitArming.PipeVerifyArmingScenario.Armed` (the ambient environment plus its marker and log), which requires `fatal=1` on the arming line |
 | 2026-10-18 | unit `PipeInputsTest.{PoisonOmitKnobArmsTheOmission, BadPoisonOmitKnobIsFatalNamingTheKnob}`, and the `MOBILEGL_PIPE_POISON_OMIT` knob: `Features.PipePoisonOmit`, its parser on every verb (`MGPipeValidateForVerb`'s `ParsePoisonOmissionKnob`, compiled into every build) and the server stamp's own parse of it | Test / unit (every poison lane); product code | the knob existed only for negative control B, and the two cases pinned its parser and its `Fatal{PipeVerifyBadKnob}` | the PoisonOmitted and VerifySplitPoisonOmitted entries set the harness marker `MGITEST_POISON_OMIT` to the same pair, and the re-executed child arms it through `MGPipeSetPoisonOmission`, compiled only with `-DMOBILEGL_PIPE_VERIFY=ON` (`Harness/PoisonOmissionArm.h`); `OmittingOneFieldForOneVerbLeavesExactlyThatFieldStale`, `ReadingAnOmittedFieldAbortsNamingTheVerb` and `TheMutationNoticeRefreshesTheValueButNotTheStamp` withhold the stamp test-side and still run in every poison lane; the setter's scope to its verb, not its class, is checked by `OmittingOneFieldForOneVerbLeavesExactlyThatFieldStale` in a forked child, on the verify runtime only |
 | 2026-10-18 | the `serial == resets` assertion of `CtWireScenario.ApplierResetCrossesAtThePrimedEdgeInSerialOrder`, and the `MOBILEGL_TEST_SERVER_COUNTERS` knob: `ServerMain`'s `MGPipe server counters:` line on every LogFlush and `ServerVerbSink`'s test-only tallies (`ApplierResets`, `ObjectDeaths`, `ExpectedApplierResetSerial`) | Test / `integration-split`, `integration-split-strict`, `integration-verify-split`, `integration (inproc)`; product code | the knob existed only so the spawn and tcp arms could read the sink's tallies; the serial assertion could not fail, since `OnApplierReset` moves the count and the serial together and any other serial latches `Fatal{ProtocolCorruption, "ApplierReset.ContextSerial"}` | `ar` / `od` on the server role's `MGPipe stats:` line, counted in `ServerVerbSink::OnApplierReset` / `OnObjectDeath`; every CtWire entry that counts them sets `MOBILEGL_PIPE_STATS=1` with period 1 and reads them on every arm, inproc included, over a window closed by a swap and a readback; the unit cases `ApplierResetWireRoundTrip.TheSerialSequenceIsAssertedAndTheServerResetRuns` and `ObjectDeathWireRoundTrip.TheTextureAndFramebufferTwinsReleaseByHandleAndNeverByAStaleGeneration` read the same counters, and the first shows the expected serial moving by having serial 2 accepted |
+| 2026-11-15 | per-case jobs `retrace (<backend>, <case>)`, `retrace verify (<backend>, <case>)`, `retrace split (<backend>, <case>, <transport>)` | Test / `retrace`, `retrace-verify`, `retrace-split` | one runner per case spent most of its time on setup; no case, knob, assertion or arm proof is dropped | shard jobs that replay the same rows one after another through `scripts/ci/retrace_shard.py`, one ctest entry and one verdict per case; `trace_cases.py --self-test-shard-matrices` checks that the shards hold exactly the per-case rows |
+| 2026-11-15 | per-case emulator jobs `retrace (<backend>, <case>)` of each lane | MobileGL APK / `retrace` | one emulator boot per replay; no case, setting or arm proof is dropped | shard jobs that replay the cases of one lane, transport and backend on one boot through `android-plugin/trace_replay_shard.py`, with app data cleared between cases, a cold boot after a case that did not pass, and one verdict per case |
+| 2026-11-15 | per-case `trace fixture (<case>)` jobs, their per-case cache entries and artifacts, `.github/scripts/trace-fixture-cache.sh` | Test and MobileGL APK / `trace-fixtures` | 40 jobs and 40 cache entries per workflow for files that change rarely | one content-addressed cache entry for all Git LFS fixtures (`.github/scripts/trace-fixture-bundle.sh`); a replay job restores it and downloads a case only when the entry does not hold it |
+| 2026-11-15 | `remove-artifact-clutter` job | Test and MobileGL APK | it deleted the fixture artifacts and the green result artifacts after the run; the fixture artifacts no longer exist | the delete step at the end of `retrace-summary`; on Linux `retention-days: 1` on the summary inputs as well, `retrace-split` and `retrace-shipped` upload results only for a failed shard (their green results were deleted unread before), and `retrace-verify` keeps its results for every shard as before |
 
 ## Kept after investigation