refactor(browser): move the browser server into its own entity

[sheremet-va]

Description

All browser-related logic is now moved into @vitest/browser package. vitest/node exposes a BrowserServer interface that is implemented by @vitest/browser so we don't need to bundle those types together if @vitest/browser is not used.

There are no more browserProvider/browserRpc/browserState/browserMocker on the workspace project class.

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Tests

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Documentation

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Changesets

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