Add Error Handling

[abhibongale]

Add comprehensive error handling throughout StackBox with helpful error messages that guide users to solutions. Handle common failure scenarios gracefully.

Goals

• Catch and handle common errors
• Provide actionable error messages
• Suggest fixes for problems
• Improve user experience

Common Errors to Handle

Docker not running

try:
    subprocess.run(["docker", "ps"], check=True, capture_output=True)
except:
    click.echo("❌ Docker not running")
    click.echo("   Start with: sudo systemctl start docker")
    sys.exit(1)

Ports already in use

if port_in_use(6385):
    click.echo("❌ Port 6385 already in use")
    click.echo("   Check: lsof -i :6385")
    sys.exit(1)

Insufficient resources

if disk_space_gb() < 20:
    click.echo("⚠️  Low disk space (< 20GB)")
    click.echo("   Clean up: docker system prune")

Acceptance Criteria

• All subprocess calls have error handling
• Error messages are helpful
• Suggests solutions
• No raw Python tracebacks shown to user
• Exit codes are appropriate

Testing

Test each error scenario and verify helpful message is shown.