night13: close #148 as not-a-bug on the tracker

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018SgmXGNMXavXiafKXf9MDC

scratchpad/night13/close148.py

@@ -0,0 +1,81 @@
+"""Night 13: close #148 as not-a-bug with the measured chain.  ASCII only."""
+import sys
+sys.path.insert(0, r"C:\git\bt411\scratchpad\night7")
+import gitea
+
+BODY = """**NOT A BUG -- closing (2026-08-08).** There was nothing to fix here. The bench was lying,
+and this ticket's own premise was wrong twice over.
+
+## The answer
+
+`Entity::Execute` (`ENTITY.cpp:556`, real engine source [T0]) calls `PerformAndWatch` **only** when
+
+```cpp
+application->GetApplicationState() == Application::RunningMission
+ || application->GetApplicationState() == Application::EndingMission
+ || IsPreRunnable()
+```
+
+and otherwise merely `WriteSimulationUpdate()`s. `Entity::DefaultFlags` is
+`DynamicFlag|MasterInstance` -- **no `PreRunFlag`**. Only `Player` and `Director` add it in their
+DefaultFlags, and `Mech::Reset` sets it for a reset MASTER ("a reset master must tick"). A
+**replicant mech never gets it.**
+
+So a peer mech performs **zero** subsystem ticks until the round actually starts, no matter how
+much correctly-replicated data is arriving for it. Measured on the observer node:
+
+```
+ 235  [perf-first] mech 3:161 master      <- own mech, immediately
+ 402  [torso-rec-rx]                      <- peer's torso records start arriving
+2754  [perf-first] mech 2:55 REPLICANT    <- peer's FIRST performance
+2758  [torso] PushTwist COPY              <- its torso ticks 4 lines later
+2761  [ent-exec] state=5                  <- RunningMission
+```
+
+The peer starts performing exactly at the RunningMission transition. That is the engine doing
+what it says it does.
+
+## So the symptom was a BENCH ARTIFACT
+
+`BT_AUTOFIRE` starts shooting immediately, during `WaitingForLaunch` -- something no player can do
+in a real match. Those leading salvos measured a peer whose torso, gait and subsystems had never
+run. Every `ZZZZ...XXXX` prefix in this investigation was that, and the first `X` lands within a
+few lines of the state transition.
+
+**#141 is unaffected and stays fixed** -- its segment-cache defect was real and mid-match.
+
+## Ruled out along the way (all measured, all recorded so nobody repeats them)
+
+* **The record cadence is authentic.** My "only 13 records in 5 minutes" premise was wrong. The
+  payloads are the sweep EXTREMES with `rate` flipping sign at each one -- the master sends on
+  **rate change** and the peer dead-reckons `atUpd + rate * elapsed` between them. 12 records for
+  12 direction reversals is correct, not starved.
+* **The `ComputeTargetTwist` clamp.** The copy's limits load correctly (`limL=2.44346
+  limR=-2.44346 enab=1`), so `Min/Max` was not pinning `targetTwist` to zero.
+* **The torso's own executable flag.** `Entity::Perform` picks its predicate by instance
+  (`IsNonReplicantExecutable` vs `IsReplicantExecutable`, differing on
+  `|| lastUpdate >= lastPerformance`), and Mech's tick loop had dropped that branch. Restoring it
+  (`f36f013`) is a genuine fidelity fix and is kept -- but it moved this bug by nothing.
+* **The scheduler.** The replicant entity IS offered to the performer with `executable=1` from
+  line 171, ~2500 lines before its first `PerformAndWatch`. The gate was inside `Execute`, not in
+  who gets offered.
+
+## What came out of it
+
+* `[perf-first]` -- a one-shot per-mech receipt naming entity ID + instance at a mech's first
+  performance. Every other per-frame receipt in mech4 is anonymous, which is exactly why this took
+  so long to see in a 2-node log.
+* `[torso-copy]` now prints `limL/limR/enab`; `[launchframe]` prints the shooter's live torso twist.
+* **Gotcha #29** in `context/reconstruction-gotchas.md`: judge a 2-node bench by PREFIX vs
+  INTERLEAVED, never by raw percentage; check `[ent-exec] state=` before suspecting replication.
+  `missileframe.sh` carries the same warning inline.
+
+## Still worth checking separately
+
+`#37` (MadCat torso BACKWARDS) and `#70` (torso twist stops after respawn) were flagged here as
+possibly sharing a cause. They do **not** share this one -- it is not a defect. They should be
+re-tested against the #141 segment-cache fix instead, which is a real mid-match change."""
+
+gitea.comment(148, BODY)
+gitea.call("/issues/148", method="PATCH", payload={"state": "closed"})
+print("closed #148")