Update Issues

# Status
linear-cli i update LIN-123 -s Done
linear-cli i update LIN-123 -s "In Progress"

# Priority
linear-cli i update LIN-123 -p 1    # 1=urgent, 2=high, 3=normal, 4=low

# Assignee
linear-cli i update LIN-123 -a me
linear-cli i update LIN-123 -a "John Doe"

# Labels
linear-cli i update LIN-123 -l bug
linear-cli i update LIN-123 -l bug -l urgent