feat(profile): let users design their public profile

README.md

@@ -50,7 +50,9 @@ To Be Played is split into three repositories:
   the proved Steam ID, never a typed-in one. A Steam ID typed in before shows as "not verified" with a button to
   verify it; unlinking is possible.
 - **Public profile** at `/u/<display name>`, opt-in in the settings, with perfect games and average completion.
-  The user picks in the settings which stat groups of "Your stats" it shows (none by default).
+  The user picks in the settings which stat groups of "Your stats" it shows (none by default), and designs its
+  look: accent, corners, banner and background from own game art ("Profile art" on a game's page), and which
+  sections it shows in which order. Visitors see the owner's look on that page only; light or dark mode stays theirs.
 - **Appearance**: accent color, corner style, wide layout, page background and banner from your own game art.
   Saved in Auth, so it follows you to every device.
 - **Broken pictures**: a Steam cover or achievement icon that does not load shows a placeholder and is reported