fix: split view focus (#11217)

# After:

https://github.com/user-attachments/assets/990d500d-2da7-488e-ac32-dd7bd229f896

# Before:

https://github.com/user-attachments/assets/6676766a-c76a-414b-a35e-53d2cda10c24

blocksuite/affine/shared/src/commands/selection/focus-block-end.ts

@@ -19,6 +19,7 @@ export const focusBlockEnd: Command<{
 
   const { selection } = std;
 
+  std.event.active = true;
   if (force) selection.clear();
 
   selection.setGroup('note', [