generalize the protocol to return errors, etc.

Dependencies

• [2] BSDXVB3H backport some doc updates and renames
• [3] VCLH24QJ update protocol so driver shows syntax errors
• [4] LRDM35CE app running again
• [5] BZDYEW4M don't also send success on error

Change contents

• replacement in live.lua at line 281
  [3.8032]→[2.868:898](∅→∅)
  − live.send_to_driver('ok')
  [3.8032]

  [3.8032]
  + live.send_to_driver('{}')