Nozzle guard in stop mode (brush log-only), wait for the nozzle before HOME

Test print start: guard peaks 1-8 in every phase except the brush scrub
(peak 47, 4 reads above 30 in a row), 0 I2C errors; a light finger push
gives 41. Stop mode for all phases, the brush stays log-only.

The contact homing in HOME restarted 6 times (sample spread too large)
while the nozzle was still heating to 150C; PRINT_WARMUP now waits for a
steady contact temperature first, as PRINT_START does.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

CLAUDE.md

@@ -97,8 +97,10 @@ detection, `filament_error_sensitivity`), iHeater chamber heater.
   13-18 s, peak 64-181; empty nozzle about 30 ms. A real failed load in a
   print start (AFC reported the lane loaded, nothing reached the nozzle):
   longest 1915 ms, peak 45, caught by the 5000 ms limit.
-- Nozzle guard (bdp_guard): reading at rest and in travel peaks about 2; a
-  light finger push on the cold nozzle gives 41 (threshold 30).
+- Nozzle guard (bdp_guard): peaks 1-8 in home_xy, QGL, Z homing, mesh and
+  the Z check; the brush scrub 47 (4 reads above 30 in a row, so it runs
+  in log mode); a light finger push on the cold nozzle gives 41
+  (threshold 30).
 - Z check after a contact homing: Beacon vs Klipper Z about 0.06 mm.
 - XY drift check: endstop noise about 0.01-0.02 mm; limit 0.1 mm (one motor
   skipping one cycle = 0.4 mm shows as 0.2 mm in X and Y).