[#19]

Add interactive setup wizard and connectivity test commands for improved CLI UX.

Summary

• Add jtk init command for interactive guided setup wizard
  • Prompts for URL, email, and API token
  • Verifies connection before saving (--no-verify to skip)
  • Supports non-interactive mode via flags
  • Detects existing config and prompts for overwrite
• Add jtk config test command for connectivity verification
  • Tests authentication and API access
  • Provides clear pass/fail status with troubleshooting suggestions

Usage

# Interactive setup
jtk init

# Non-interactive setup
jtk init --url https://mycompany.atlassian.net --email user@example.com --token YOUR_TOKEN

# Test connection
jtk config test

Test plan

• All existing tests pass
• Lint passes
• Manual testing of jtk init --help
• Manual testing of jtk config test
• Verified connectivity test works with real Jira instance

Closes #19