Add a STOP CONDITION to the TRANSMIT MESSAGE 'Perform Command' for applicable units

[TEMPEST.114]

There is no option to STOP the currently transmitting message via a STOP CONDITION for the PERFORM COMMAND -> TRANSMIT MESSAGE function inside the Mission Editor or Scripting.

If you had both a START and a STOP condition, then interactive and dynamic communications could happen between players and AI aircraft, by having multiple TRANSMIT MESSAGES stacked up, each with their own START and STOP conditions.