Support Custom Launch Configurations

[JustinGrote]

Is your feature request related to a problem? Please describe.
I am authoring a cloudflare worker with an end-to-end test that starts workerd on a custom inspect port. When clicking the "debug" button, vitest uses its own custom debug launch config and I have no way to set up to attach to the workerd instance in order to debug internals.

Describe the solution you'd like
Provide a configuration option to supply a custom debug launch config, similar to the Mocha Test Explorer. vitest would then append its -t, --api-port, and --api-host to the args of that launch config.

Alternatively, provide an additional attach port setting in the config that will launch a child attach debug config on the specified port.

I would be willing to attempt a PR if there is interest, I wrote my own Test Extension for PowerShell Pester and am familiar with the internals.

[sheremet-va]

In the new extension (pre-release 0.5.0+), we attach to the process that runs Vitest instead of starting a new process. Do you think your proposal could still work with that approach?