chore(assets): remove dead icon assets and consolidate icons/

Delete zero-referenced leftovers (31 img SVGs, duplicate top-level
vip badges, favicon/icon/person_background pngs, assets/fonts/,
tmp-debug/, gutenberg-extend.js and the FA eot/ttf/svg font formats)
and give icon-purpose SVGs one home in assets/icons/ (upload-add,
default favicon/logo, playing, user-certification) with every reference
updated. Icon SVG files were audited by name across PHP/CSS/JS before
deletion.

assets/css/main.css

@@ -8545,7 +8545,7 @@ body.modal-open .float-btn.wait-pay-btn .hover-show-con {
 .switch-iframe.active .episode-active-icon,
 .switch-video.active .episode-active-icon {
     /* clean-css ignore:start */
-    background-image: url(../img/playing.svg);
+    background-image: url(../icons/playing.svg);
     /* clean-css ignore:end */
     width: 1em;
     margin-right: 6px;