SteelTailor profile: use G41/G40 controller-side kerf comp, matching the proven file exactly

Corrected call: the earlier "leave kerf to Kiri's own tool-diameter
field" choice wasn't wrong about double-compensation risk (doing both
at once genuinely would double-offset the cut), but replicating the
already-proven controller-side approach exactly is the lower-risk
starting point - it doesn't depend on whoever runs a job correctly
dialing in a matching diameter in Kiri every time, and it's known-good.

No code change needed - G41 goes in gcodeSpindle right before M07, G40
in gcodeSpindleOff right after M08, using the per-cut hook already
built. Matches the proven file's exact bracket order per cut.

src/kiri/dev/cam/SteelTailor.Plasma.json

@@ -17,10 +17,12 @@
     ],
     "gcodeDwell": [],
     "gcodeSpindle": [
+        "G41 ; cutter compensation on - kerf value lives in the controller's own tool table, not this file",
         "M07 ; torch on"
     ],
     "gcodeSpindleOff": [
-        "M08 ; torch off"
+        "M08 ; torch off",
+        "G40 ; cutter compensation off"
     ],
     "gcodeChange": [],
     "gcodeFExt": "nc",