feat: add interactive home dashboard

[cotore-game]

Summary

• launch an ASCII-art whiptail dashboard when mcserver-kit is run interactively without arguments
• manage servers, creation, global settings, MCID templates, language, diagnostics, and help from one menu
• preserve direct subcommands and show help for non-interactive no-argument execution
• include the dashboard in installation and release archives

Verification

• 96 specification tests passed (1 ZIP test skipped locally because zip is not installed)
• locale catalog validation passed
• Bash and Python syntax checks passed
• Docker-based ShellCheck passed

This change is intended for the v1.0.0 release.