Type-to-filter when watching

[Quantumplation]

I was doing some development on a repo with a lot of tests, and working to make the test pass, and found myself continually having to scroll up to view the test.

It'd be cool if I could start typing like a fuzzy matcher while in --watch mode, if that set a filter on the tests to run, as if you had set -m, --match-tests.

Then, I could type out withdraw_fees and then continue developing, and have it just continually run the withdraw_fees tests, rather than all tests.