[SVG export with globally unique clip-path IDs]

Hi! I recently noticed an issue with inline SVG code that Affinity Designer outputs. It uses a very simple naming convention, and you get ID conflicts when you have two or more SVGs inline. This causes one SVG to use masks from another SVG and things get proper broken at this point.

Affinity Designer could write globally unique IDs to SVGs to fix the issue. This could be an option in export, as I understand file size may be more precious at some scenarios.