[WIP] Run tests with Bloop when the build server wasn't disabled

[Gedochao]

When the build server wasn't disabled with --server=false, we could be running tests with Bloop.
Of course, test-runner and java-test-runner would still be used with --server=false.

Checklist

• tested the solution locally and it works
• ran the code formatter (scala-cli fmt .)
• ran scalafix (./mill -i __.fix)

How much have your relied on LLM-based tools in this contribution?

Extensively

How was the solution tested?

split the test command integration tests into dedicated suites, with and without Bloop tested separately

[Gedochao]

This needs a Bloop bump when it's out to bring scalacenter/bloop#2938 in.