docs: add experimental mode to compatibility description (#26954)

* docs: add experimental mode to compatibility description

* lower case

selfdrive/car/docs_definitions.py

@@ -204,6 +204,13 @@ class CarInfo:
       if self.row[Column.STEERING_TORQUE] != Star.FULL:
         sentence_builder += " This car may not be able to take tight turns on its own."
 
+      # experimental mode
+      exp_link = "<a href='https://blog.comma.ai/090release/#experimental-mode' target='_blank' class='link-light-new-regular-text'>Experimental mode</a>"
+      if CP.openpilotLongitudinalControl or CP.experimentalLongitudinalAvailable:
+        sentence_builder += f" Traffic light and stop sign handling is also available in {exp_link}."
+      else:
+        sentence_builder += f" {exp_link}, with traffic light and stop sign handling, is not currently available for this car, but may be added in a future software update."
+
       return sentence_builder.format(car_model=f"{self.make} {self.model}", alc=alc, acc=acc)
 
     else: