feat: 移除未使用的消息处理函数和Markdown插件任务创建功能，优化代码结构

app/Http/Controllers/Api/DialogController.php

@@ -3245,55 +3245,6 @@ class DialogController extends AbstractController
         return Base::retSuccess('success', $topMsg);
     }
 
-    /**
-     * @api {get} api/dialog/msg/applied 标记消息已应用
-     *
-     * @apiDescription 需要token身份
-     * @apiVersion 1.0.0
-     * @apiGroup dialog
-     * @apiName msg__applied
-     *
-     * @apiParam {Number} index         索引
-     * @apiParam {Number} msg_id        消息ID
-     *
-     * @apiSuccess {Number} ret     返回状态码（1正确、0错误）
-     * @apiSuccess {String} msg     返回信息（错误描述）
-     * @apiSuccess {Object} data    返回数据
-     */
-    public function msg__applied()
-    {
-        User::auth();
-        //
-        $msg_id = intval(Request::input('msg_id'));
-        $index = intval(Request::input('index'));
-        //
-        $msg = WebSocketDialogMsg::whereId($msg_id)->first();
-        if (empty($msg)) {
-            return Base::retError("消息不存在或已被删除");
-        }
-        WebSocketDialog::checkDialog($msg->dialog_id);
-        //
-        $originalMsg = $msg->getRawOriginal('msg');
-        $pattern = '/:::\s*(create-task-list|create-subtask-list)(?:\s+(\S+))?/';
-        $count = -1;
-        $updatedMsg = preg_replace_callback($pattern, function($matches) use (&$count, $index) {
-            $count++;
-            if ($count === $index || ($index === 0 && $count === 1)) {
-                return "::: {$matches[1]} applied";
-            }
-            return $matches[0];
-        }, $originalMsg);
-
-        if ($count === -1) {
-            return Base::retError("未找到可应用的规则");
-        }
-
-        $msg->msg = $updatedMsg;
-        $msg->save();
-        //
-        return Base::retSuccess("success");
-    }
-
     /**
      * @api {get} api/dialog/sticker/search 搜索在线表情
      *

app/Models/WebSocketDialogMsg.php

@@ -695,7 +695,6 @@ class WebSocketDialogMsg extends AbstractModel
                 $text = $title;
             } else {
                 $text = Base::markdown2html($text);
-                $text = self::previewConvertTaskList($text);
             }
         }
         $text = preg_replace("/<img\s+class=\"emoticon\"[^>]*?alt=\"(\S+)\"[^>]*?>/", "[$1]", $text);
@@ -711,36 +710,6 @@ class WebSocketDialogMsg extends AbstractModel
         return $text;
     }
 
-    /**
-     * 转换任务列表
-     * @param $text
-     * @return array|string|string[]|null
-     */
-    private static function previewConvertTaskList($text) {
-        $pattern = '/:::\s*(create-task-list|create-subtask-list)(.*?):::/s';
-        $replacement = function($matches) {
-            $content = $matches[2];
-            $lines = explode("\n", trim($content));
-            $result = [];
-            $currentTitle = '';
-            foreach ($lines as $line) {
-                $line = trim($line);
-                if (empty($line)) continue;
-
-                if (preg_match('/^title:\s*(.+)$/', $line, $titleMatch)) {
-                    $currentTitle = $titleMatch[1];
-                    $result[] = $currentTitle;
-                } elseif (preg_match('/^desc:\s*(.+)$/', $line, $descMatch)) {
-                    if (!empty($currentTitle)) {
-                        $result[] = $descMatch[1];
-                    }
-                }
-            }
-            return implode("\n", $result);
-        };
-        return preg_replace_callback($pattern, $replacement, $text);
-    }
-
     /**
      * 预览文件消息
      * @param $msg