hasTrailingCodeExecutionResult

Returns true if the last part of this event is a code-execution result. Mirrors ADK Java's Event.hasTrailingCodeExecutionResult().

The Kotlin Part type does not yet model codeExecutionResult (see com.google.adk.kt.types.Part). Until it does, this helper is always false. The clause is still present in isFinalResponse so that the call structure matches Java verbatim and so a future Part.codeExecutionResult field is wired into the right gate by construction.