Check port availability when generating config.toml

[chriscarrollsmith]

Is your feature request related to a problem? Please describe. I've encountered an issue where the Supabase CLI auto-generates a config.toml file with default port settings. If those ports are already in use on the system (for instance, by another Supabase instance or different services), it leads to conflicts. For those of us who develop semi-regularly on Supabase, it's natural to have multiple local databases already running in Docker, which means we have to manually change the ports in config.toml.

Describe the solution you'd like It would be great if the Supabase CLI could check the availability of default ports when generating the config.toml file. If a default port is already in use, the CLI could automatically assign an available port. This feature would streamline the setup process, making it more user-friendly and efficient, especially for developers working with multiple Supabase instances or on systems with several services running.

Describe alternatives you've considered If a port is taken, the CLI could prompt the user to specify an alternative port. This is a little more effortful on the user's part, though.

Additional context This feature would particularly help in development environments where developers are likely to run multiple instances of services for different projects. Automating the process of checking and assigning available ports would significantly reduce setup time and potential frustration due to port conflicts.