tools+docs: the flight pad was writing into a dead file - every autopilot input went nowhere

flight_probe.Pad opened /tmp/sylph-vgamepad.fifo, "the vgamepad server's FIFO".
That server was removed when the uinput pad was replaced by Canary's --hid=file
driver, because a uinput device is not namespaced and scripted presses leaked to
the host's desktop. The FIFO is now an ordinary 91-byte file nothing reads, and
/tmp/xenia_pad.txt - the file the emulator polls - was 0 bytes while the
"autopilot" was flying. So every axis, trigger and button from pilot.py,
autopilot3.py, aim_probe.py and flight_probe.py went nowhere, silently.

The corpus already carried this trap for the SHELL scripts
(canary-scripted-input-traps.md, "every call here failed silently"). This class
was missed, and every flight tool imports it.

Verified against the oracle rather than by inspection, on runs confirmed
animating at both ends of every phase: before, full stick produced 0.00 degrees
of heading change over 4 s while the ship travelled 350-735 units, and the
attitude matrix at pos-0x70 was byte-identical; after, LX=-1 turns 12.72 degrees
and LX=+1 swings the flight direction from [1,0,0] to [0.13,-0.14,-0.98], with
the matrix moving 0.44/0.31 under stick and 0.0000 at neutral.

That also REFUTES the "stale attitude matrix" suspicion from the earlier pass -
pos-0x70 is live and tracks the ship; it only looked dead because nothing was
turning the ship.

Still open and said plainly: with the pad fixed a 150 s pilot run still fires 0
times, with |aim yaw| still exactly 90.0 and the target 36-43 km away. Steering
works now, so what is left is the stick SIGN against the pilot's error convention
or a target selection that commits to something too far to close. Both are
finally testable.

findrot_global/findself/findspeed/selfstate still write to the dead FIFO and now
say so in place; they are not repaired because none has been re-run since.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PMRJjbxLqZtsb5Vb7KunPE

docs/re/pilot-never-fires.md

@@ -1,7 +1,11 @@
 # `pilot.py` never pulls the trigger — the proximal cause, measured
 
-**Status: ✅ the gate that blocks it is identified and measured; 🔴 the root cause
-is not, and one attempt to find it was invalidated by a freeze.**
+**Status: ✅ ROOT CAUSE FOUND AND FIXED (2026-08-23, later the same day) — the
+flight tools' pad wrote to a FIFO nothing has read since the uinput pad was
+removed, so every stick, trigger and button they sent went nowhere.** The gate
+measured below is real; it was open because the craft was never being flown at
+all. 🟡 The pilot still does not converge on a target in 150 s with the input
+working — see the last section.
 
 ## The observation
 
@@ -75,3 +79,69 @@ Re-run `aim_probe.py` on a run confirmed to be animating **at the end of the
 probe as well as the start** — the tool should check `frozen.py` itself and
 discard the phase otherwise. If the matrix does move under stick, the question
 becomes the sign; if it does not, the binding is what to chase.
+
+
+---
+
+# ✅ ROOT CAUSE — the flight tools' pad was writing into a dead file
+
+`flight_probe.Pad` opened **`/tmp/sylph-vgamepad.fifo`** and wrote
+`axis LX 0.850`-style lines to it, described in its own docstring as "the vgamepad
+server's FIFO". That server does not exist any anymore: the uinput pad was removed
+because a uinput device is **not namespaced** and every scripted press leaked to
+the *host's* desktop, and it was replaced by Canary's `--hid=file` driver. The
+FIFO is now an ordinary 91-byte file that nothing reads.
+
+Meanwhile `/tmp/xenia_pad.txt` — the file the emulator actually polls — was
+**0 bytes** while the "autopilot" was supposedly flying.
+
+So every axis, trigger and button from `pilot.py`, `autopilot3.py`,
+`aim_probe.py` and `flight_probe.py` itself went into a dead file, silently, and
+the craft flew on its own for the whole of every run. That is why the target sat
+astern at 90.0° forever and the range grew to 49 km: **the ship was never being
+turned.**
+
+**The corpus already carried this trap — for the other half of the toolkit.**
+[`canary-scripted-input-traps.md`](canary-scripted-input-traps.md) records
+"pad.py, NOT `vgamepad`: that command no longer exists … and every call here
+failed silently, so the whole scripted route pressed nothing". The **shell**
+scripts were fixed then. This class was not, and every flight tool imports it.
+
+## Measured, before and after
+
+Same probe, on runs confirmed animating at both ends of every phase
+([`aim_probe.py`](../../tools/re-capture/aim_probe.py) brackets each phase with
+`frozen.py` now, after a freeze voided the first attempt):
+
+| | heading change under full stick | attitude matrix `pos-0x70` |
+|---|---|---|
+| **before** | `0.00°` in every phase, over 4 s, while travelling 350–735 units | `d 0.0000` — unchanged |
+| **after** | `12.72°` on `LX=-1`; `LX=+1` swings the flight direction from `[1,0,0]` to `[0.13,-0.14,-0.98]` | `d 0.4438` / `d 0.3108` under stick, `0.0000` at neutral |
+
+🔴 **So the "stale attitude matrix" reading is refuted**, and with it the earlier
+suspicion that the binding was wrong: `pos-0x70` is live and tracks the ship. It
+only looked dead because nothing was turning the ship.
+
+## 🟡 Still open — the pilot does not converge
+
+With the pad fixed, a 150 s `pilot.py` run still fired **0** times: over its 86
+targeted samples `|aim yaw|` is *still* exactly 90.0° and the range is
+36–43 km. Steering now works, so what remains is one of:
+
+* the **sign** of the yaw stick against the pilot's own error convention — a
+  controller that turns away from the error would hold `ez < 0` forever, which is
+  exactly the observed signature;
+* target selection that keeps committing to something 40 km away, which at
+  ~300 units/s cannot be closed inside the window.
+
+Both are now testable, because the input path finally works. The measurement to
+make is the direct one: command the pilot's own `sx` for a known error and see
+whether `|yaw|` falls or rises.
+
+## Not fixed, and flagged in place
+
+`findrot_global.py`, `findself.py`, `findspeed.py` and `selfstate.py` still write
+to the dead FIFO. Each now carries a comment saying so and pointing here. They
+are not repaired because none of them has been re-run since, and quietly changing
+the input plumbing under a tool whose results are unverified would only
+manufacture new unverified results.