Detect and use the next available port after 3000 when starting Evidence dev server

[mcrascal]

Fine tuning -- not for current release

If you launch the dev server while localhost:3000 is occupied elsewhere, evidence will launch on localhost:3001 -- the simple browser preview that the extension opens should respect the new development url.

[RandomFractals]

Agreed. Occupied port discovery was something I planned to look into. However, I only saw your app use port 3000 and all the docs state so in command examples. So, I thought it's the default and only port your users use.

We already have host forwarding enabled for GitHub Codespaces (#21).

We'll add dynamic port finding in the next release too.

[RandomFractals]

.@mcrascal: does Evidence dev server simply try the next available port after 3000?

Per your CLI docs, we can pass --port parameter to npm exec evidence dev command we issue to VS Code terminal to start Evidence app dev server with the next available port we find after 3000.

[RandomFractals]

• Add httpUtils.ts to extension src/utils/ for all http related APIs: available port detection, ping, etc.

[mcrascal]

@RandomFractals yes

https://vitejs.dev/config/server-options.html#server-port

[RandomFractals]

This feature is almost complete. We just need to resolve the 5001 port increment disconnect when rewriting preview page url and opening it in a simple browser. We already detect free port and pass it as param to the start server command via terminal.

@archiewood created a good capture of the increment port disconnect here: #52 (comment)

[RandomFractals]

• This is not fully resolved due to vite server and our free port detection and the server start command we send being out of sync.
• The way I see it, finalizing this feature is nice to have when we have more time to troubleshoot it.
• There is a workaround that users can use and set different evidence.defaultPort value in the new Evidence extension settings.
• Also, listed in our new Limitations section in docs: https://github.com/evidence-dev/evidence-vscode#limitations
• Will not fix in Sprint 2 for the v1.1.0 enhancements and improved onboarding user experince, but can take a look at this later in Sprint 3, if we have time for this nice to have feature