[Prachi24599]

Closes #3045

Summary

Fixes the cursor jumping to the wrong Checklist item when pressing Backspace after clicking between items.

Problem

When a user clicks one Checklist item, then clicks another item and presses Backspace, the cursor can jump to an incorrect item because currentInput may reference a previously focused input.

Solution

• Added a click event handler to update the current input after the browser updates the selection.
• Clear the cached inputs before updating currentInput.
• Removed the click event listener when the block is destroyed to prevent event listener leaks.

Testing

• Reproduced the issue using eight Checklist items.
• Verified that clicking between items and pressing Backspace keeps the cursor in the correct item.
• yarn build passed.
• yarn lint passed with 0 errors (30 warnings).