feat(admin): 订单详情查找订阅链接支持一键绑定（携带 attach_order_id）

tests/Feature/AdminPlatformOrderShowFindSubscriptionLinkShouldCarryAttachOrderIdTest.php

@@ -0,0 +1,73 @@
+<?php
+
+namespace Tests\Feature;
+
+use App\Models\Merchant;
+use App\Models\Plan;
+use App\Models\PlatformOrder;
+use Illuminate\Foundation\Testing\RefreshDatabase;
+use Tests\TestCase;
+
+class AdminPlatformOrderShowFindSubscriptionLinkShouldCarryAttachOrderIdTest extends TestCase
+{
+    use RefreshDatabase;
+
+    protected function loginAsPlatformAdmin(): void
+    {
+        $this->seed();
+
+        $this->post('/admin/login', [
+            'email' => 'platform.admin@demo.local',
+            'password' => 'Platform@123456',
+        ])->assertRedirect('/admin');
+    }
+
+    public function test_find_subscription_link_should_carry_attach_order_id_and_attach_back(): void
+    {
+        $this->loginAsPlatformAdmin();
+
+        $merchant = Merchant::query()->firstOrFail();
+        $plan = Plan::query()->create([
+            'code' => 'po_show_find_sub_attach_order_plan',
+            'name' => '订单详情 查找订阅链接携带 attach_order_id 测试套餐',
+            'billing_cycle' => 'monthly',
+            'price' => 30,
+            'list_price' => 30,
+            'status' => 'active',
+            'sort' => 10,
+            'published_at' => now(),
+        ]);
+
+        $order = PlatformOrder::query()->create([
+            'merchant_id' => $merchant->id,
+            'plan_id' => $plan->id,
+            'order_no' => 'PO_SHOW_FIND_SUB_ATTACH_ORDER_0001',
+            'order_type' => 'renewal',
+            'status' => 'pending',
+            'payment_status' => 'unpaid',
+            'plan_name' => $plan->name,
+            'billing_cycle' => $plan->billing_cycle,
+            'period_months' => 1,
+            'quantity' => 1,
+            'payable_amount' => 30,
+            'paid_amount' => 0,
+            'placed_at' => now(),
+            'meta' => [],
+        ]);
+
+        $res = $this->get('/admin/platform-orders/' . $order->id);
+        $res->assertOk();
+
+        $html = (string) $res->getContent();
+
+        // 仍应包含 merchant_id/plan_id/back
+        $this->assertStringContainsString('/admin/site-subscriptions?', $html);
+        $this->assertStringContainsString('merchant_id=' . $merchant->id, $html);
+        $this->assertStringContainsString('plan_id=' . $plan->id, $html);
+        $this->assertStringContainsString('back=' . urlencode('/admin/platform-orders/' . $order->id), $html);
+
+        // 新增：应携带 attach_order_id/attach_back，支持订阅列表行内一键绑定并回跳
+        $this->assertStringContainsString('attach_order_id=' . $order->id, $html);
+        $this->assertStringContainsString('attach_back=' . urlencode('/admin/platform-orders/' . $order->id), $html);
+    }
+}