Implement disconnectedCallback() and disconnect() lifecycle cleanup for custom elements

[piraz]

Implement the disconnectedCallback() lifecycle method for custom elements to handle cleanup when the component is removed from the DOM. This method must:

• Check if the component is still considered 'connected' (using a custom connected() method).
• If connected, remove the comment element from its parent if it exists.
• Call a custom disconnect() method for further cleanup (such as removing listeners, freeing resources, etc.).

Also, implement the disconnect() method as a placeholder for custom cleanup logic. It should be empty by default but documented for extension.

This ensures proper cleanup and extensibility for custom elements in the codebase.