revert hyundai canfd torque to stock; park-publish keepalive; dashcam idle on park

Three independent changes bundled together.

Revert hyundai canfd steering torque limits to comma stock defaults
(270 / 2 / 3 / 112) in both panda safety and openpilot CarControllerParams.
The 270->324 bump caused overcorrection on turns and weaving on straights.
Web research turned up no public reports of any 4th gen Tucson NX4 owner
bumping STEER_MAX — the documented Tucson tuning effort is entirely on
lateralTuning (latAccelFactor ~2.9-3.1, friction ~0.095), not the cap.
hoomoose's EV6/Ioniq 5 PR #25723 is the canonical "raise STEER_MAX
without dropping latAccelFactor causes overcorrection" data point — and
even that change was reverted upstream. Right next move for this car is
to tune latAccelFactor / friction, not the torque ceiling.

plannerd: keep publishing longitudinalPlan at the normal cadence in park,
but skip update() compute. Skipping publishes entirely caused
longitudinalPlan to time out the alive flag at controlsd, which fired a
real commIssue ("not_alive") on park->drive. Stale published values are
fine because controlsd's own park short-circuit ignores the
longitudinalPlan content while parked. Also gate publish_ui_plan on
not-parked: it reads longitudinal_planner.a_desired_trajectory_full
which is only set inside update(), so calling it without a prior update
crashes plannerd with AttributeError (which fires "Process Not Running"
on screen). uiPlan is UI-only, not on controlsd's commIssue check list,
so going silent in park is fine.

frogpilot_process: same idea — keep publishing frogpilotPlan in park to
keep alive, skip the heavy update() compute.

dashcamd: close the trip immediately on gear shift to PARK (was: 10-min
idle timer before close). User wants the dashcam idle in park and a
fresh trip on every drive engagement; brief drive-thru / fuel-stop
across-trip continuity isn't valued.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

selfdrive/controls/plannerd.py

@@ -34,13 +34,21 @@ def plannerd_thread():
   while True:
     sm.update()
     if sm.updated['modelV2']:
-      # CLEARPILOT: skip planning while parked. The downstream consumer (controlsd)
-      # already short-circuits in park, so longitudinalPlan/uiPlan staleness is fine.
-      if sm['carState'].gearShifter == car.CarState.GearShifter.park:
-        continue
-      longitudinal_planner.update(sm)
+      # CLEARPILOT: skip the planning compute while parked, but KEEP publishing
+      # at the normal cadence so consumers' alive flags stay healthy. Skipping
+      # publishes entirely caused longitudinalPlan to go alive=False at
+      # controlsd, which fires a real commIssue the moment we shift out of park.
+      # Stale published values are fine — controlsd's own park short-circuit
+      # ignores the longitudinalPlan content while parked anyway.
+      parked = sm['carState'].gearShifter == car.CarState.GearShifter.park
+      if not parked:
+        longitudinal_planner.update(sm)
       longitudinal_planner.publish(sm, pm)
-      publish_ui_plan(sm, pm, longitudinal_planner)
+      # publish_ui_plan reads longitudinal_planner.a_desired_trajectory_full
+      # which is only set inside update(). Skip it while parked — uiPlan is
+      # UI-only, not on controlsd's commIssue check list, so going silent is fine.
+      if not parked:
+        publish_ui_plan(sm, pm, longitudinal_planner)
 
 def main():
   plannerd_thread()