bench: the controller port and manual home harnesses

Two host harnesses for the grblHAL driver's null-sink build, in the bench
registry and the README with the others. The driver's CI runs them.

ctlport_test.py drives the controller port beside a scripted Grbl sender
that counts every ok and error it is sent, which is the only way to see a
status routed to the wrong source. 13 cases: the socket's mode; a port
jog's status going to the port with the sender's count exact and the jog
run whole under the sender's '?' polls; a port error the sender's next line
does not inherit; the sender's line canceling a fast port jog and drawing
its own ok (fast on purpose: a slow jog stops at once and would pass with no
hold at all); a sender line queued right behind the port's; the refusals;
one client, and five reconnects right after a close; the status hook across
a soft reset; the dead-man; a CR LF sender; a sender that polls the way
LightBurn does, '?' with an end of line behind it, LF and CR LF (every port
jog accepted, a 60 mm port jog run whole with the polls landing inside it,
one ok per poll, a real line still canceling a port jog); and every
operation of both sets under an open armed window with M3 modal and S500,
where the dump must hold no FIRE tick.

manual_home_test.py reads the stream dump (GFSINK_DUMP) and the attribute
log (GFSINK_ATTR_LOG), so it can say that nothing was shipped and which
current was written, and how many times. 9 cases: a manual $H ships no step
and no FIRE tick and declares the offsets with the soft limits on and Z
kept; $H refused in a cycle; $MD refused under an open armed window with
nothing written; every motion source and $X refused while released; each
energize written exactly once; the port's panel operations; both pairs of
home offsets, alone and at once; and a controller killed under a release,
whose replacement writes only 0 and 0.

Both pass against the driver's extensions tree. The poll cases fail against
the driver without its empty-line rule ("8 of 8 port jogs were refused under
a status poll"), which is the defect they were written from: it was found
on the bench reference with LightBurn connected, and the sender these
harnesses had until then polled a bare '?'.

scripts/bench/README.md

@@ -33,6 +33,8 @@ page's takeover does that; from a host, stop them first.
 | `laser_stream_test.py` | Host-side laser pulse-stream emission harness: runs the native null-sink controller with `GFSINK_DUMP`, drives small laser jobs over TCP, and checks the dumped bytes against the kernel feeder contract (leading power byte, no back-to-back power bytes, FIRE only inside cutting moves, every stream ends FIRE-clear, no FIRE on a stepless gap, no FIRE leak across cycle churn, the rapids after an M5 executed at idle ship dark, and the next job in the same process fires at the level the previous one ended at). Runs in the grblHAL repo's CI. |
 | `laser_lifecycle_test.py` | Host-side operator-armed-window lifecycle harness (null-sink controller): arm once per job with M5/M3 persistence, the M2 close, sender-change re-consent, the disarm grace counting down in Hold, and arm refusal under a blocking cooling verdict. Runs in the grblHAL repo's CI. |
 | `z_envelope_test.py` | Host-side Z envelope harness (null-sink controller): the Z soft limit belongs to the driver, not to `$20`, so the driver re-applies `sys.work_envelope`, `sys.homed` and `sys.soft_limits` for Z from the settings-changed chain. Checks that an unreferenced Z is collapsed to where the lens stands and blocks a move each way, that X and Y stay free, and that neither a `$20` write (the core clears the soft-limit mask in the setter) nor a `$132` write (which un-homes the axis as well) frees Z. Runs in the grblHAL repo's CI. |
+| `ctlport_test.py` | Host-side controller port and line-multiplexer harness (null-sink controller): a scripted sender that counts every `ok` and `error` runs beside the port's one client on `grbl.ctl`. A port jog's status goes to the port and never to the sender, a port error does not reach the sender's parser, a sender line cancels a port jog and gets its own `ok` (a line queued right behind the port's included), plus the refusals, the single client, a CR LF sender, a soft reset, and the client as the dead-man. `python3 ctlport_test.py <grblHAL_glowforge>`. |
+| `manual_home_test.py` | Host-side manual homing and motor release harness (null-sink controller, `GFSINK_DUMP` and `GFSINK_ATTR_LOG`): `$H` under `homing_mode = manual` ships nothing and declares X0 Y0; while the motors are released (`$MD`) every motion source is refused and ships nothing, `$X` and a soft reset do not unlock it, and only `$ME` and a manual `$H` write the energize. Imports its sender and port client from `ctlport_test.py`. `python3 manual_home_test.py <grblHAL_glowforge>`. |
 | `live_fire_drills.py` | **LIVE LASER** drills, on the board (the bench page) or from a LAN host (`GF_HOST`): `live_fire_drills.py <drill> [S] [F]` - `witness` (emission witness, lid-IR peaks vs the ambient baseline, HV current, job-based disarm on M2), `hold` (disarm grace in Hold), `faultpos` (armed job refuses a stale origin after an underrun), `ircut` (lid-IR characterization cut at S/F), `pthresh` (laser power-threshold ladder: 13 constant-power rungs from 2 % to 30 % of full on scrap; the lowest rung that marks is the tube's striking threshold and reads directly as the `$35` value - requires `$35` = 0 for the run), `dladder` (density ladder at a chosen base period), `pcurve` (laser performance-curve ladder: one 100 mm line per level at 10 mm/s under M3, the laser off between rungs and a mid-ladder rung repeated at the end; reads `pic/hv_current` and the head thermopile `head/beam_detect_analog` (a scatter detector in the beam path upstream of the final mirror, so it sees the beam, not the material) from sysfs at ~25 Hz on the board, brackets each rung on the controller's Run/Idle states, and reports per rung the current with a clipped-at-1023 flag, the thermopile delta over its laser-off baseline and in-line drift, then the normalized curve, monotonicity, a line fit with its threshold intercept and the repeat-rung drift; JSON record with the raw trace in the bench data directory; rungs follow `laser_power_model`, a comma list overrides; a curve measurement wants `$35` = 0), `dpatch [F] [pitch] [length]` (depth witness for the density dose curve: two rows of small serpentine-filled patches, row A CW at feeds giving relative doses 1.0 to 0.25 of the reference feed, row B at the reference feed at 100/80/60/45/30 % density; the operator matches each row-B patch to the row-A patch of equal depth, which reads the density's light fraction off the material beside the thermopile's prediction; JSON record), `m4feeds [S] [F1] [F2]` (the density time base across feeds: one out-and-back line pair per feed at the same S under M4 density, one armed run; the operator reads within-line evenness and reversal darkness at both feeds - M4's velocity scaling is what holds dose per mm through the accel), `m4corner [S] [F]` (M4 velocity-scaled power into corners: a corner-heavy vector pattern at 30 % under M4 density, one armed run; the operator confirms every commanded segment marks - the floor makes a dropout unreachable - and the drill asserts the arm report, one discharge window and dark after), `m5dark` (the rapids after an M5 ship dark: one 20 mm line at M3 S400, M5, dwell, rapid back, dwell, rapid forward; PASS when the 25 Hz current trace shows one discharge segment and reads dark after the M5 and `laser_on_sampled` never re-lights; the catalog's `laser.m5-rapid-dark` is its port), `flowload` (cooling under laser load, one armed run per invocation, the conf keys it writes put back at the end, the pump never commanded off: `t1` reproduces the flow-check trip with the check on at its defaults and two 30 x 4 mm CW fills at F1500 starting on the press with no dark dwell, and reports the engine's rise/dT verdict beside the 25 Hz trace of both coolant sensors, the current, the digital witness and the heater output in 5 s bins across the window, with the shape at fire start; `t2 <secs> [pct]` runs with the check off and one fill of about `secs` lit seconds at CW or at `pct` density, and reports the lag to each sensor, the rise per raw-second of `hv_current` and what a full 50 s window would add against the 1.6 C margin; `fit` fits rise against dose over every t2 record; JSON records), `expstop` (armed kill on the expected-stop path; needs the panel token - `GF_TOKEN`, or the board's token file) and `ctrlstart` (the separate controller restart after it). Every drill waits for the operator's physical arm press; eye protection, fire watch, extinguisher, and exhaust are mandatory. |
 | `pacing_test.py` | Protocol-loop pacing check (runs on the board, dry motion): idle and parked-in-Hold states are coarse-paced, active motion is tight-paced, and a feed-hold/resume mid-move preserves position with no feeder starve. |
 | `planner_blocks_test.py` | Host-side planner buffer depth harness (null-sink controller): `$398` written to 400 and to 1000, the controller restarted on the same settings store each time, and it must answer on the port, report the depth in its status report and run a move. A byte-wide ring index once made 255 blocks or more spin the start. Runs in the grblHAL repo's CI. |