Improve: subscription index filter links keep context without nesting back

resources/views/admin/site_subscriptions/index.blade.php

@@ -14,6 +14,25 @@
         $selfWithoutBack .= '?' . \Illuminate\Support\Arr::query($currentQuery);
     }
     $back = $selfWithoutBack;
+
+    // 用于构建“保留当前筛选上下文”的站内跳转链接（且不透传 back，避免嵌套/污染）
+    $buildSelfUrl = function (array $overrides = []) use ($currentQuery) {
+        $q = $currentQuery;
+        foreach ($overrides as $k => $v) {
+            if ($v === null) {
+                unset($q[$k]);
+            } else {
+                $q[$k] = $v;
+            }
+        }
+
+        $url = '/' . ltrim(request()->path(), '/');
+        if (count($q) > 0) {
+            $url .= '?' . \Illuminate\Support\Arr::query($q);
+        }
+
+        return $url;
+    };
 @endphp
 <div class="card mb-20">
     <p class="muted muted-tight">这里是总台视角的订阅目录页，承接“套餐 -> 订阅 -> 平台订单”的收费主链中间层。</p>
@@ -139,14 +158,14 @@
                 </td>
                 <td>
                     @if($subscription->merchant)
-                        <a class="link" href="/admin/site-subscriptions?merchant_id={{ $subscription->merchant->id }}">{{ $subscription->merchant->name }}</a>
+                        <a class="link" href="{{ $buildSelfUrl(['merchant_id' => $subscription->merchant->id, 'page' => null]) }}">{{ $subscription->merchant->name }}</a>
                     @else
                         未关联站点
                     @endif
                 </td>
                 <td>
                     @if($subscription->plan)
-                        <a class="link" href="/admin/site-subscriptions?plan_id={{ $subscription->plan->id }}">{{ $subscription->plan_name ?: $subscription->plan->name }}</a>
+                        <a class="link" href="{{ $buildSelfUrl(['plan_id' => $subscription->plan->id, 'page' => null]) }}">{{ $subscription->plan_name ?: $subscription->plan->name }}</a>
                     @else
                         {{ $subscription->plan_name ?: '未设置' }}
                     @endif