Missing Error Code for Invalid Callsign #99
Description
Current behavior:
$ python3 interlocutor.py 'INVALID CALL!'
❌ Error: Invalid characters in callsign: , !
Thank you for using Opulent Voice!
$ echo $?
0 # ← Should be 1 for error
Desired behavior:
$ python3 interlocutor.py 'INVALID CALL!'
❌ Error: Invalid characters in callsign: , !
$ echo $?
1 # ← Proper error exit code