feat(receivables): fresh receivables implementation

app/Domains/Receivables/Http/Requests/SendPaymentRequest.php

@@ -0,0 +1,35 @@
+<?php
+
+namespace App\Domains\Receivables\Http\Requests;
+
+use Illuminate\Foundation\Http\FormRequest;
+
+/**
+ * The composed receipt mail: an envelope and a body, both written by the
+ * sender. Copies are optional.
+ */
+class SendPaymentRequest extends FormRequest
+{
+    /**
+     * The send ability is checked by the controller, against the payment.
+     */
+    public function authorize(): bool
+    {
+        return true;
+    }
+
+    /**
+     * @return array<string, mixed>
+     */
+    public function rules(): array
+    {
+        return [
+            'subject' => ['required'],
+            'body' => ['required'],
+            'from' => ['required'],
+            'to' => ['required'],
+            'cc' => ['nullable'],
+            'bcc' => ['nullable'],
+        ];
+    }
+}