fix(badges): complete full-chain badge circuit and preset icons

Close the full circuit break in the badge/medal system and replace
empty default icons with preset SVG assets so badges render out of
the box:

- Add aksrt_get_worn_medal_icon() helper that renders the worn medal
  image inline (with settings fallback when the Badges class is
  unavailable).
- Profile header (UC) now shows the worn medal icon beside the name,
  matching zibll's name row order (display_name → VIP → Medal → Level → Verify).
- Add .medal-icon / .aksrt-identity-medal vertical-align rules in UC shell.css.
- Extract SchemaUsers::default_medal_args() and preset 6 badges (rookie,
  checkin-30, writer, popular, annual-star, vip-member) with real icon
  URLs from assets/img/medal/ (medal-1/2/5/9/12/15.svg).
- Vue badge.js: add MEDAL_BASE helper + preset icons matching PHP defaults.

inc/helpers/user-center-renderers/profile-header.php

@@ -41,6 +41,10 @@ extract($context, EXTR_SKIP); // phpcs:ignore WordPress.PHP.DontExtract.extract_
 				if ($vip_badge) {
 					echo $vip_badge; // phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped
 				}
+				// Worn medal icon inline to the right of the name (zibll parity).
+				if (function_exists('aksrt_get_worn_medal_icon')) {
+					echo aksrt_get_worn_medal_icon((int) $user_id); // phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped
+				}
 				// Level icon inline to the right of the name (zibll parity).
 				if (class_exists('\AKSRT\User\Level') && method_exists('\AKSRT\User\Level', 'get_badge_html')) {
 					echo \AKSRT\User\Level::get_badge_html((int) $user_id); // phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped