I need an experienced PrestaShop specialist to move my shop from version 8.1.3 to 9.0 without disrupting sales or design. Scope of work • Create and store a full backup of all files and the database before touching production. • Verify that the server stack (PHP 8.2 / MySQL) meets every 9.0 requirement and flag any gaps. • Preserve the existing theme, custom overrides, and every third-party module currently installed; if one will not run on 9.0, propose an equivalent replacement. • Run the in-place upgrade, resolve 500 errors, cache or override conflicts, and any other issues that surface. • Test both the front office and the back office, then push the live site immediately once everything is stable (no separate staging step is required). I will provide FTP and database credentials as soon as the project is awarded. Please outline your approach, estimated turnaround time, and any previous PrestaShop 8→9 upgrade experience when you respond.