zdiff3 for merge conflicts

modules/cli/git.nix

@@ -50,6 +50,7 @@ in {
                             init.defaultBranch = cfg.defaultBranch;
                             push.autoSetupRemote = true;
                             commit.verbose = true;
+                            merge.conflictstyle = "zdiff3";
                             interactive.diffFilter = "${pkgs.delta}/bin/delta --color-only";
                         };
                     }