[WIP] Add command to open dev server in a side panel

[Princesseuh]

Changes

This adds a command to open the currently running dev server / a new one if there's none in a side panel in the editor. This is powered by VS Code's simple-browser (HMR is supported, clicking between the pages work etc). It loads the user's config using Proload to get the user's specified port if there's any

Some users were actually already doing this by using VS Code's Simple Browser command, however they had to start the dev server separately and type in the address manually

Testing

Tested manually on Windows and Linux

Our test setup for VS Code is currently not setup in a way that allows this to be tested as it doesn't load a project. Additionally, in a lot of way it would feel like testing things outside our world (is Proload loading the config? Does VS Code's browser work?)

Docs

No docs needed (added commands are documented in the "Feature contributions" tab on the extension page inside VS Code automatically)

[changeset-bot[bot]]

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Latest commit: 686357d84b081f887af72f04f52029c2dcda9590

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[Princesseuh]

Closing due to inactivity, the code ended up being weirdly complicated anyway. Astro does not use proload anymore to load the Astro config either, so maybe we need to find another solution (could be great if Astro itself gave the port to us)