Better arrangement choices for a frontend to enumerate pick-list options

In reference to a post by @sonninnos in https://github.com/libretro/RetroArch/pull/16960#discussion_r1759653679

Options that might get packaged with RetroArch, like a theme color, font, default core overlay, global shader, menu background or navigation sounds, screensaver, etc.

I've always liked those GUI pick-list items for community-based or plug-in options that sort by a "popularity" rating, then by date "added" -- allows for an author to put the first 5-star vote on a release so it sorts at the top until subsequent votes come in, instead of it falling unceremoniously to the bottom when it is appended.

Internally, the option continues as a fixed integer for backward compatibility, but obviously, the change is adding the metadata (and a community popularity poll database) for frontend(s) to implement this arrangement -- also motivates frontend(s) to modernize. If nothing else changes, it simply continues to work AS-IS.

Start by reading the discussion linked from PR 16960, especially the referenced post and comment. Define how metadata for pick-list options and a community popularity database would support frontend arrangement by popularity and date while preserving the existing fixed-integer behavior; the issue is done only when that design and its implementation scope are clear.