fix(navigation): align mega-menu rendering and menu-item backend with the reference

Renderer:
- Graphic-card images carry fit-cover so they crop into the fixed card box
  instead of stretching it and pushing the title out of alignment.
- Mega-menu link icons use fa-fw (fixed glyph column) instead of the
  undefined menu-item-icon class, so link titles line up.

Backend:
- Restore show_policy (login / vip / vip_2 / auth) on menu items; the field
  was missing entirely, so items could not be gated by identity.
- Default submenu_type to graphic_card, badge_class to jb-red, arrangement
  to swiper, size to md.
- Clamp img_scale to 20-300 to match the reference's spinner bounds.
- Drop the now-meaningless "none" submenu_type option: the senior-submenu
  switch is itself the on/off control.
- Admin JS gains the align control (left/center/space-around).

Cleanup:
- Remove the unused header_actions nav menu location.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

src/Admin/NavMenuOptions.php

@@ -46,8 +46,9 @@ class NavMenuOptions {
 		$icon = (string) ($opts['icon'] ?? '');
 		$badge = (string) ($opts['badge'] ?? '');
 		$badge_class = (string) ($opts['badge_class'] ?? '');
+		$show_policy = (string) ($opts['show_policy'] ?? '');
 		$submenu_s = !empty($opts['submenu_s']);
-		$submenu_type = (string) ($opts['submenu_type'] ?? '');
+		$submenu_type = (string) ($opts['submenu_type'] ?? 'graphic_card');
 		$graphic_json = !empty($opts['graphic_card_opts'])
 			? wp_json_encode($opts['graphic_card_opts'], JSON_UNESCAPED_UNICODE | JSON_PRETTY_PRINT)
 			: self::sample_graphic_json();
@@ -83,6 +84,19 @@ class NavMenuOptions {
 					value="<?php echo esc_attr($badge_class); ?>">
 			</label>
 		</p>
+		<p class="field-jio-show-policy description description-wide">
+			<label for="edit-menu-item-jio-show-policy-<?php echo esc_attr((string) $item_id); ?>">
+				<?php esc_html_e('显示限制', 'jio'); ?><br>
+				<select id="edit-menu-item-jio-show-policy-<?php echo esc_attr((string) $item_id); ?>"
+					class="widefat" name="jio_menu_options[<?php echo esc_attr((string) $item_id); ?>][show_policy]">
+					<option value="" <?php selected($show_policy, ''); ?>><?php esc_html_e('不限制', 'jio'); ?></option>
+					<option value="signin" <?php selected($show_policy, 'signin'); ?>><?php esc_html_e('登录后显示', 'jio'); ?></option>
+					<option value="vip" <?php selected($show_policy, 'vip'); ?>><?php esc_html_e('所有会员显示', 'jio'); ?></option>
+					<option value="vip_2" <?php selected($show_policy, 'vip_2'); ?>><?php esc_html_e('二级会员显示', 'jio'); ?></option>
+					<option value="auth" <?php selected($show_policy, 'auth'); ?>><?php esc_html_e('认证用户显示', 'jio'); ?></option>
+				</select>
+			</label>
+		</p>
 		<p class="field-jio-submenu description description-wide">
 			<label>
 				<input type="checkbox" name="jio_menu_options[<?php echo esc_attr((string) $item_id); ?>][submenu_s]" value="1" <?php checked($submenu_s); ?>>
@@ -94,9 +108,8 @@ class NavMenuOptions {
 				<?php esc_html_e('高级子菜单类型', 'jio'); ?><br>
 				<select id="edit-menu-item-jio-submenu-type-<?php echo esc_attr((string) $item_id); ?>"
 					name="jio_menu_options[<?php echo esc_attr((string) $item_id); ?>][submenu_type]">
-					<option value="" <?php selected($submenu_type, ''); ?>><?php esc_html_e('无', 'jio'); ?></option>
 					<option value="graphic_card" <?php selected($submenu_type, 'graphic_card'); ?>><?php esc_html_e('图文卡片', 'jio'); ?></option>
-					<option value="multi_column_links" <?php selected($submenu_type, 'multi_column_links'); ?>><?php esc_html_e('多列链接', 'jio'); ?></option>
+					<option value="multi_column_links" <?php selected($submenu_type, 'multi_column_links'); ?>><?php esc_html_e('多栏目链接', 'jio'); ?></option>
 				</select>
 			</label>
 		</p>
@@ -134,6 +147,7 @@ class NavMenuOptions {
 			'icon'         => jio_sanitize_icon_value((string) ($raw['icon'] ?? '')),
 			'badge'        => sanitize_text_field((string) ($raw['badge'] ?? '')),
 			'badge_class'  => sanitize_html_class((string) ($raw['badge_class'] ?? '')),
+			'show_policy'  => self::sanitize_show_policy((string) ($raw['show_policy'] ?? '')),
 			'submenu_s'    => !empty($raw['submenu_s']),
 			'submenu_type' => sanitize_key((string) ($raw['submenu_type'] ?? '')),
 		];
@@ -150,6 +164,15 @@ class NavMenuOptions {
 		update_post_meta($menu_item_db_id, 'jio_menu_options', $clean);
 	}
 
+	/**
+	 * @param string $policy
+	 */
+	private static function sanitize_show_policy(string $policy): string {
+		$allowed = ['', 'signin', 'vip', 'vip_2', 'auth'];
+		$policy = sanitize_key($policy);
+		return in_array($policy, $allowed, true) ? $policy : '';
+	}
+
 	/**
 	 * @return array<string,mixed>|null
 	 */
@@ -177,7 +200,7 @@ class NavMenuOptions {
 				'img'   => esc_url_raw((string) ($item['img'] ?? '')),
 				'title' => sanitize_text_field((string) ($item['title'] ?? '')),
 				'badge' => sanitize_text_field((string) ($item['badge'] ?? '')),
-				'badge_class' => sanitize_html_class((string) ($item['badge_class'] ?? '')),
+				'badge_class' => sanitize_html_class((string) ($item['badge_class'] ?? 'jb-red')),
 				'link'  => [
 					'url'    => esc_url_raw((string) ($item['link']['url'] ?? '')),
 					'text'   => sanitize_text_field((string) ($item['link']['text'] ?? '')),
@@ -186,10 +209,10 @@ class NavMenuOptions {
 			];
 		}
 		return [
-			'arrangement' => sanitize_key((string) ($opts['arrangement'] ?? '')),
+			'arrangement' => sanitize_key((string) ($opts['arrangement'] ?? 'swiper')),
 			'align'       => sanitize_key((string) ($opts['align'] ?? '')),
-			'size'        => sanitize_key((string) ($opts['size'] ?? '')),
-			'img_scale'   => max(0, min(200, (int) ($opts['img_scale'] ?? 100))),
+			'size'        => sanitize_key((string) ($opts['size'] ?? 'md')),
+			'img_scale'   => max(20, min(300, (int) ($opts['img_scale'] ?? 100))),
 			'items'       => $items,
 		];
 	}
@@ -240,7 +263,7 @@ class NavMenuOptions {
 
 	private static function sample_graphic_json(): string {
 		$sample = [
-			'arrangement' => '',
+			'arrangement' => 'swiper',
 			'size' => 'md',
 			'img_scale' => 100,
 			'items' => [