fix(admin): replicate reference comment settings page 1:1

- Rewrite post_list/comment schema (PHP + JS) with the reference theme's
  field set, order, defaults and dependencies; smilie, comment location
  and quick-reply fields excluded
- Map PostDisplay::get_comment_display_settings() to the new keys without
  legacy fallback: close_comments, comment_paginate_type (ajax_lists),
  user_edit_comment master switch, WP comment_order for sorting
- Wire comment_box_hide visibility gate (signin / vip / vip_2 / auth)
- Drop dead comment settings (order/per_page/depth/avatar/hot threshold/
  empty text/city), the dead post_close_comments field, and city readers
  now fully owned by the IP-geo extension
- Add comment settings reference contract test

inc/helpers/comments/geo.php

@@ -3,7 +3,7 @@
  * Comment city / IP geo helpers.
  *
  * Meta: aksrt_comment_addr {country,province,city}
- * Gates: ip_geo_enabled + ip_geo_display has comment + comment_city_s
+ * Gates: ip_geo_enabled + ip_geo_display has comment（扩展&增强 / IP归属地统一控制）
  *
  * @package AKSRT
  */
@@ -12,27 +12,14 @@ defined('ABSPATH') || exit;
 
 if (!function_exists('aksrt_comment_city_enabled')) :
 	function aksrt_comment_city_enabled(): bool {
-		if (function_exists('aksrt_ip_geo_display_enabled') && !aksrt_ip_geo_display_enabled('comment')) {
-			return false;
-		}
-		if (!class_exists('\AKSRT\Settings\Settings')) {
-			return false;
-		}
-		$s = \AKSRT\Settings\Settings::get_comment_display_settings();
-		return !empty($s['city_s']);
+		// 评论区位置显示的开关与精度统一由「扩展&增强 / IP归属地」配置提供。
+		return function_exists('aksrt_ip_geo_display_enabled') && aksrt_ip_geo_display_enabled('comment');
 	}
 endif;
 
 if (!function_exists('aksrt_comment_city_type')) :
 	function aksrt_comment_city_type(): string {
-		if (!class_exists('\AKSRT\Settings\Settings')) {
-			return function_exists('aksrt_ip_geo_format_key') ? aksrt_ip_geo_format_key() : 'province_city';
-		}
-		$s = \AKSRT\Settings\Settings::get_comment_display_settings();
-		$type = sanitize_key((string) ($s['city_type'] ?? 'province_city'));
-		return in_array($type, ['province_city', 'province', 'country_province'], true)
-			? $type
-			: 'province_city';
+		return function_exists('aksrt_ip_geo_format_key') ? aksrt_ip_geo_format_key() : 'province_city';
 	}
 endif;