[browser] move console proxy from runtime code into test-main

[pavelsavara]

• after we know how to inject it via dev server
• chrome driver is probably forwarding enough console to be able to skip it completely
• geckodriver is not forwarding any console logs (maybe this is configuration issue)
  • for that reason, some of the messages need to be duplicated in test-main, only after the proxy was already setup

[dotnet-policy-service]

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[ilonatommy]

After #109069 we don't use test-main anymore. Can we close it?

[pavelsavara]

We still use test-main to run normal library unit tests. And this issue is about forwarding the console log, which FF doesn't do with geckodriver. So I think we can't