Fix/earth rover dataset features (#3088)

* docs(earthrover): update EarthRover Mini Plus dataset features and descriptions

* refactor(teleop): rename rover action keys to linear_velocity/angular_velocity

* fix(earthrover): align observation and action features with frodobots/berkeley-frodobots-lerobot-7k

* chore: address PR review comments

* ci: retrigger checks

src/lerobot/teleoperators/keyboard/teleop_keyboard.py

@@ -341,8 +341,8 @@ class KeyboardRoverTeleop(KeyboardTeleop):
     def action_features(self) -> dict:
         """Return action format for rover (linear and angular velocities)."""
         return {
-            "linear.vel": float,
-            "angular.vel": float,
+            "linear_velocity": float,
+            "angular_velocity": float,
         }
 
     @property
@@ -366,7 +366,7 @@ class KeyboardRoverTeleop(KeyboardTeleop):
         Get the current action based on pressed keys.
 
         Returns:
-            RobotAction with 'linear.vel' and 'angular.vel' keys
+            RobotAction with 'linear_velocity' and 'angular_velocity' keys.
         """
         before_read_t = time.perf_counter()
 
@@ -427,6 +427,6 @@ class KeyboardRoverTeleop(KeyboardTeleop):
         self.logs["read_pos_dt_s"] = time.perf_counter() - before_read_t
 
         return {
-            "linear.vel": linear_velocity,
-            "angular.vel": angular_velocity,
+            "linear_velocity": linear_velocity,
+            "angular_velocity": angular_velocity,
         }