fix(platform): 修复由于使用的Think-Captcha版本不同造成的验证码的问题

src/app/platform/controller/Login.php

@@ -99,11 +99,34 @@ class Login extends Controller
      */
     public function captcha()
     {
-        $captcha_data = ThinkCaptcha::create(null, true);
+        // 生成验证码ID
         $captcha_id = md5(uniqid(null, true));
         // 验证码10分钟有效
-        Cache::set($captcha_id, $captcha_data[ 'code' ], 600);
-        return success(0, '', [ 'id' => $captcha_id, 'img' => $captcha_data[ 'img' ] ]);
+        $expire = 600;
+        
+        try {
+            // 尝试使用版本3.x的方式
+            $captchaInstance = new \think\captcha\Captcha(app()->make('config'), app()->make('session'));
+            $captchaInstance->configure();
+            $generator = $captchaInstance->generate();
+            $code = $generator['value'];
+            $captchaResponse = ThinkCaptcha::create();
+            
+            // 获取图片内容
+            ob_start();
+            $captchaResponse->send();
+            $imgContent = ob_get_clean();
+            // 生成base64图片
+            $imgBase64 = 'data:image/png;base64,' . base64_encode($imgContent);
+        } catch (\Exception $e) {
+            // 如果失败，尝试使用版本2.x的方式
+            $captchaData = ThinkCaptcha::create(null, true);
+            $code = $captchaData['code'];
+            $imgBase64 = $captchaData['img'];
+        }
+        
+        Cache::set($captcha_id, $code, $expire);
+        return success(0, '', [ 'id' => $captcha_id, 'img' => $imgBase64 ]);
     }
 
     /**