fix(cloud): rework unsubscribed team cleanup and account deletion (#12210)

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>

database/migrations/2026_10_19_101103_add_ended_at_to_subscriptions_table.php

@@ -0,0 +1,30 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\DB;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    public function up(): void
+    {
+        Schema::table('subscriptions', function (Blueprint $table) {
+            $table->timestamp('ended_at')->nullable()->index()->after('stripe_refunded_at');
+        });
+
+        // updated_at is the best available estimate for rows that ended before this column existed.
+        DB::table('subscriptions')
+            ->where('stripe_invoice_paid', false)
+            ->where('stripe_past_due', false)
+            ->update(['ended_at' => DB::raw('updated_at')]);
+    }
+
+    public function down(): void
+    {
+        Schema::table('subscriptions', function (Blueprint $table) {
+            $table->dropIndex(['ended_at']);
+            $table->dropColumn('ended_at');
+        });
+    }
+};