modeld two-state; UI: immediate blank on ignition off; READY splash on wake

- modeld: simplified to 0fps (standstill or parked) or 20fps. Removed
  4/10fps reduced-rate path, republish caching, FPCC/liveCalibration
  reads, and ModelFps per-cycle param writes.
- ui.cc updateWakefulness: ignition on→off now resets interactive_timeout
  to 0 for immediate screen blank. Tap still wakes via existing handler.
- home.cc offroadTransition(false): reset ready->has_driven to false so
  the READY text appears on fresh ignition, not the textless post-drive
  splash.

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

selfdrive/ui/qt/home.cc

@@ -122,9 +122,11 @@ void HomeWindow::offroadTransition(bool offroad) {
     slayout->setCurrentWidget(ready);
   } else {
     // CLEARPILOT: start onroad in splash — updateState will switch to
-    // camera view once the car shifts out of park
+    // camera view once the car shifts out of park. Reset has_driven so
+    // fresh ignition shows the READY text (not the post-drive textless splash).
     LOGW("CLP UI: onroad transition -> showing splash (parked)");
     was_parked_onroad = true;
+    ready->has_driven = false;
     slayout->setCurrentWidget(ready);
   }
 }