cargo-rail: added an 'undo' sub-command for the 'unify' command to ensure that reversing unification is easy and low friction. added the

Author: loadingalias

Cargo.lock

@@ -39,6 +39,9 @@ rayon = "1.11.0"
 # Parsing (zero-copy, minimal deps)
 winnow = "0.7.13"
 
+# Date/time handling for backup timestamps
+chrono = "0.4"
+
 [dev-dependencies]
 tempfile = "3.23.0"