feat: add captcha-backed forum security hardening

app/Services/Security/Captcha/CaptchaProviderInterface.php

@@ -0,0 +1,18 @@
+<?php
+
+namespace App\Services\Security\Captcha;
+
+interface CaptchaProviderInterface
+{
+    public function name(): string;
+
+    public function isEnabled(): bool;
+
+    public function siteKey(): string;
+
+    public function inputName(): string;
+
+    public function scriptUrl(): string;
+
+    public function verify(string $token, ?string $ip = null): bool;
+}