What hook/filter can I use to add/edit/show/hide the title under (on hover) links on the table view?

You will want to use the post_row_actions filter https://developer.wordpress.org/reference/hooks/post_row_actions-2/

For example, to add a link, you could try something like:

function add_custom_link($actions, $page_object)
{
    $actions['custom_link'] = '<a href="http://www.example.com">My Custom Link</a>';

   return $actions;
}

add_filter('post_row_actions', 'add_custom_link', 10, 2);

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)