mathlib

2af08364 - refactor(number_theory/zsqrtd): replace `zsqrtd.conj` with `star` (#18572)

refactor(number_theory/zsqrtd): replace `zsqrtd.conj` with `star` (#18572) This allows more existing lemmas to be used; notably, `unitary (zqsrt d)` becomes something we can talk about.