Having honed my prowess in web development- specifically JavaScript and PHP- I assure you a seamless solution to implement drag-and-drop functionality for your sortable `<div>`s. My 8-year experience in the field, especially working with HTML5 and CSS3, has enabled me to offer fluid user experiences (UX) and UI, which includes interactive designs and smooth transitions.
Moreover, my proficiency with MySQL ensures quick and efficient database updates, essential for maintaining the correct positioning of the `<div>`s as they're dragged and dropped. I also have extensive knowledge and hands-on experience with AJAX, which is crucial considering your specific requirements such as the real-time update of IDs in the database whenever there's a change in sort order.
Your mention of "potential future work" aligns perfectly with my objective to establish long-term professional relationships built on trust, transparency, and quality deliverables. Client satisfaction is at the core of every project I undertake, so rest assured I'll put in my utmost effort to meet your expectations in terms of timely completion without compromising on the high standards that define my work ethic. Let's begin this project journey together!