fix(track-changes): match fallback in mark lookup to prevent per-keystroke splitting

The `|| ''` fallbacks added to mark creation caused a mismatch with
findTrackedMarkBetween lookups that still passed raw `user.email`
(undefined when no user is set). `'' === undefined` fails, so each
keystroke generated a new tracked-change ID instead of reusing the
adjacent mark's ID.

Author: caio-pizzol

packages/super-editor/src/editors/v1/extensions/track-changes/trackChangesHelpers/markDeletion.js

@@ -29,7 +29,7 @@ export const markDeletion = ({ tr, from, to, user, date, id: providedId }) => {
     from,
     to,
     markName: TrackDeleteMarkName,
-    attrs: { authorEmail: user.email },
+    attrs: { authorEmail: user.email || '' },
   });
 
   let id;

packages/super-editor/src/editors/v1/extensions/track-changes/trackChangesHelpers/markInsertion.js

@@ -21,7 +21,7 @@ export const markInsertion = ({ tr, from, to, user, date, id: providedId }) => {
     from,
     to,
     markName: TrackInsertMarkName,
-    attrs: { authorEmail: user.email },
+    attrs: { authorEmail: user.email || '' },
   });
 
   let id;