Add progress and failure indicators to Mill test runner (500USD Bounty)

[lihaoyi]

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From the maintainer Li Haoyi: I'm putting a 500USD bounty on this issue, payable by bank transfer on a merged PR implementing this.

See https://github.com/orgs/com-lihaoyi/discussions/6 for other bounties and the terms and conditions that bounties operate under

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Currently, the prompt shows the test classes that each test task is running, the duration of the task, and the duration of each test runner worker

[1427/1427] ============================== scalalib.test ============================== 54s
[1427] scalalib.test.test 25s
[1427-0] 23s mill.javalib.revapi.RevapiModuleTests
[1427-1] 23s mill.scalalib.BomTests
[1427-2] 23s mill.scalalib.AssemblyExeTests
[1427-3] 23s mill.scalalib.HelloJavaTests
[1427-4] 23s mill.scalalib.AssemblyNoExeTests

We should extend this UI in three ways:

1. Show the time each test class has been running for, on the right of that class name
2. Show the number of tests that have completed so far , on the right of the test task via the ticker
3. Show the count of test class failures so far

So it should look something like this

[1427/1427] ============================== scalalib.test ============================== 54s
[1427] scalalib.test.test 25s 14/58 completed, 5 failures
[1427-0] 23s mill.javalib.revapi.RevapiModuleTests 5s
[1427-1] 23s mill.scalalib.BomTests 4s
[1427-2] 23s mill.scalalib.AssemblyExeTests 1s
[1427-3] 23s mill.scalalib.HelloJavaTests 1s
[1427-4] 23s mill.scalalib.AssemblyNoExeTests

This should target main and be backported to 0.12.x

[HollandDM]

Hello, I had PRs ready at #4756 and #4737, please take a look