docs: remove backward compatibility notes for legacy action values

Author: lan17

concepts/controls.mdx

@@ -290,10 +290,6 @@ Fields:
 
 - `metadata`: Optional additional context (JSON object)
 
-<Note>
-  Legacy action values `allow`, `warn`, and `log` are still accepted on input but are automatically normalized to `observe`.
-</Note>
-
 ### Important: "Deny Wins" Semantics
 
 Agent Control uses "deny wins" logic: if **any** enabled control with a `deny` action matches, the request is blocked regardless of other control results. This ensures fail-safe behavior.

core/reference.mdx

@@ -72,8 +72,6 @@ Controls → Agents
 | `steer` | Raise `ControlSteerError` with steering context for correction and retry |
 | `observe` | Record the match for audit and observability without blocking execution |
 
-Legacy values `allow`, `warn`, and `log` are accepted on input but normalized to `observe`.
-
 Priority semantics:
 
 1. **Deny wins** — if any `deny` control matches, execution is blocked.