be robust to leading whitespace

Dependencies

• [2] TNRO6KLZ new live app
• [3] TK4G4GMC expose a command for the driver to remotely restart an app
• [4] BXXTVMBQ better organization of errors

Change contents

• replacement in main.lua at line 224
  [2.5776]→[2.5776:5808](∅→∅)
  − local cmd = buf:match('^%S+')
  [2.5776]

  [2.5808]
  + local cmd = buf:match('^%s*(%S+)')