rskill.yaml: declare action_contract.joint_units: radians (issue #135)

rskill.yaml

@@ -96,3 +96,8 @@ scenes:
 # to bind the LeRobot v3 `action` feature shape).
 action_contract:
   dim: 2
+  # issue #135 — EXPLICIT joint units, verified against the checkpoint normalizer
+  # stats. The skill_runner converts deg<->rad at the policy boundary; declaring
+  # it here replaces the fragile stats-magnitude guess (which drove a real arm
+  # into its limits). RADIANS = no conversion.
+  joint_units: "radians"