feat: confirm socket controls by readback

testing/fakes/src/main/kotlin/com/flagship/abox/manager/testing/fakes/FakeDeviceGateways.kt

@@ -18,6 +18,7 @@ import java.util.concurrent.CopyOnWriteArrayList
 class FakeSocketGateway : SocketGateway {
     private val states = ConcurrentHashMap<DeviceKey, SocketPowerState>()
     private val errors = ConcurrentHashMap<DeviceKey, DomainError>()
+    private val commandErrors = ConcurrentHashMap<DeviceKey, DomainError>()
 
     override suspend fun getStatus(
         profileId: ProviderProfileId,
@@ -35,11 +36,27 @@ class FakeSocketGateway : SocketGateway {
         return DomainResult.Success(SocketStatus(profileId, deviceName, powerState))
     }
 
+    override suspend fun commandPower(
+        profileId: ProviderProfileId,
+        deviceName: DeviceName,
+        powerState: SocketPowerState,
+    ): DomainResult<Unit> {
+        val key = DeviceKey(profileId, deviceName)
+        commandErrors[key]?.let { return DomainResult.Failure(it) }
+        states[key] = powerState
+        return DomainResult.Success(Unit)
+    }
+
     fun setError(profileId: ProviderProfileId, deviceName: DeviceName, error: DomainError?) {
         val key = DeviceKey(profileId, deviceName)
         if (error == null) errors.remove(key) else errors[key] = error
     }
 
+    fun setCommandError(profileId: ProviderProfileId, deviceName: DeviceName, error: DomainError?) {
+        val key = DeviceKey(profileId, deviceName)
+        if (error == null) commandErrors.remove(key) else commandErrors[key] = error
+    }
+
     private fun resultFor(
         profileId: ProviderProfileId,
         deviceName: DeviceName,