Revert #1682 (three-axis milling) (#1715)

Thanks @bherbruck.

crates/kernel/src/body.rs

@@ -1612,9 +1612,3 @@ mod display_mesh_tests;
 #[cfg(test)]
 #[path = "regularization_protection_tests.rs"]
 mod regularization_protection_tests;
-
-#[path = "body_verification.rs"]
-mod verification;
-#[cfg(test)]
-#[path = "body_verification_tests.rs"]
-mod verification_tests;