Feature: Handling Cases for User to Customer Relationships

This commit handles a case where customer data are "dead-data" menaing there is no way of erasure for them, which makes the app non-compliant

database/migrations/2026_08_24_000002_create_data_erasure_requests_table.php

@@ -25,6 +25,15 @@ return new class extends Migration
             $table->string('requested_by_type');
             $table->unsignedBigInteger('requested_by_id');
             $table->string('status')->default('pending');
+            // Set only on a Customer-scoped request that was auto-created because
+            // erasing a User left them as the sole remaining user on that Customer
+            // (see Modules\Core\Privacy\Listeners\CascadeCustomerErasureListener).
+            // Null for every normal, directly-requested erasure. Lets login-
+            // reactivation find and revert exactly the Customer request THIS
+            // User's cancellation caused, without touching an unrelated,
+            // independently-requested Customer erasure the User happens to be
+            // linked to.
+            $table->foreignId('caused_by_request_id')->nullable()->constrained('data_erasure_requests')->nullOnDelete();
             // now() + config('core.privacy.grace_period_days') at creation time —
             // when privacy:process-erasure-requests will actually run this.
             $table->timestamp('scheduled_for');