feat: Shake autodetects which module(s) to shake
There were still a few references to Mathlib in Shake, in particular it had Mathlib hardcoded as the default module to shake. Instead ask Lake what the default targets are.
(Also remove a reference to Mathlib from the help text. We still have Mathlib as an example usage, which I think is innocent enough and can stay.)
Depends on: #1204
Tested that this does the right thing on Mathlib.
Mathlib CI status (docs):
- ✅ Mathlib branch batteries-pr-testing-1205 has successfully built against this PR. (2025-04-10 14:23:48) View Log
What is the status of this PR?
My understanding is that the equivalent PR has landed in mathlib, so this PR can be closed. (If shake were to be upstreamed to batteries, #1204 should be updated.) That said, my reading of the zulip discussion was also that moving shake to batteries had no consensus, and a separate repository might be better.