feat(task): 增加解除任务关联功能

支持用户在任务详情中解除误关联的任务，权限与修改任务一致（项目负责人、任务负责人、任务协助人）。

- 新增 ProjectTaskRelation::deleteRelation() 删除双向关联并推送 WebSocket
- 新增 API POST /api/project/task/related/delete 接口
- 前端关联任务列表 hover 显示删除按钮，点击确认后解除关联

Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

app/Http/Controllers/Api/ProjectController.php

@@ -1987,6 +1987,44 @@ class ProjectController extends AbstractController
         ]);
     }
 
+    /**
+     * @api {post} api/project/task/related/delete 删除任务关联
+     *
+     * @apiDescription 需要token身份（限：项目、任务负责人）
+     * @apiVersion 1.0.0
+     * @apiGroup project
+     * @apiName task__related__delete
+     *
+     * @apiParam {Number} task_id               任务ID
+     * @apiParam {Number} related_task_id        关联任务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 task__related__delete()
+    {
+        User::auth();
+        //
+        $task_id = intval(Request::input('task_id'));
+        $related_task_id = intval(Request::input('related_task_id'));
+        if ($task_id <= 0 || $related_task_id <= 0) {
+            return Base::retError('参数错误');
+        }
+        //
+        $task = ProjectTask::userTask($task_id);
+        //
+        $project = Project::userProject($task->project_id);
+        ProjectPermission::userTaskPermission($project, ProjectPermission::TASK_UPDATE, $task);
+        //
+        $success = ProjectTaskRelation::deleteRelation($task_id, $related_task_id);
+        if (!$success) {
+            return Base::retError('关联不存在');
+        }
+        //
+        return Base::retSuccess('操作成功');
+    }
+
     /**
      * @api {get} api/project/task/content 获取任务详细描述
      *

app/Models/ProjectTaskRelation.php

@@ -143,6 +143,41 @@ class ProjectTaskRelation extends AbstractModel
         return true;
     }
 
+    /**
+     * 删除双向任务关联
+     *
+     * @param int $taskId 任务ID
+     * @param int $relatedTaskId 关联任务ID
+     * @return bool 是否删除成功
+     */
+    public static function deleteRelation(int $taskId, int $relatedTaskId): bool
+    {
+        // 删除正向关联
+        $deleted1 = static::whereTaskId($taskId)
+            ->whereRelatedTaskId($relatedTaskId)
+            ->delete();
+
+        // 删除反向关联
+        $deleted2 = static::whereTaskId($relatedTaskId)
+            ->whereRelatedTaskId($taskId)
+            ->delete();
+
+        if ($deleted1 || $deleted2) {
+            // 推送关联更新
+            $sourceTask = ProjectTask::with('project')->find($taskId);
+            $targetTask = ProjectTask::with('project')->find($relatedTaskId);
+            if ($sourceTask?->project) {
+                $sourceTask->pushMsg('relation', null, null, false);
+            }
+            if ($targetTask?->project) {
+                $targetTask->pushMsg('relation', null, null, false);
+            }
+            return true;
+        }
+
+        return false;
+    }
+
     public static function recordMentionsFromMessage(WebSocketDialogMsg $msg): void
     {
         if ($msg->type !== 'text') {

resources/assets/js/pages/manage/components/TaskDetail.vue

@@ -376,6 +376,10 @@
                                     class="related-status archived">
                                     {{$L('已归档')}}
                                 </span>
+                                <Icon
+                                    type="md-close"
+                                    class="related-remove"
+                                    @click.native.stop="removeRelatedTask(item)"/>
                             </li>
                         </ul>
                     </FormItem>
@@ -1597,6 +1601,26 @@ export default {
             this.$store.dispatch('openTask', item.related_task_id);
         },
 
+        removeRelatedTask(item) {
+            if (!item || !item.related_task_id) {
+                return;
+            }
+            $A.modalConfirm({
+                title: '温馨提示',
+                content: '确定要解除与任务 #' + item.related_task_id + ' 的关联吗？',
+                onOk: () => {
+                    this.$store.dispatch('deleteTaskRelated', {
+                        taskId: this.taskId,
+                        relatedTaskId: item.related_task_id,
+                    }).then(() => {
+                        this.loadRelatedTasks();
+                    }).catch(({msg}) => {
+                        $A.modalError(msg);
+                    });
+                },
+            });
+        },
+
         onTaskRelationUpdate(taskId) {
             if (!taskId || taskId !== this.taskId) {
                 return;

resources/assets/js/store/actions.js

@@ -2635,6 +2635,19 @@ export default {
         });
     },
 
+    deleteTaskRelated({commit, dispatch}, {taskId, relatedTaskId}) {
+        return new Promise((resolve, reject) => {
+            dispatch("call", {
+                url: 'project/task/related/delete',
+                data: {task_id: taskId, related_task_id: relatedTaskId},
+            }).then(({msg}) => {
+                commit('task/related/clear', taskId);
+                commit('task/related/clear', relatedTaskId);
+                resolve(msg);
+            }).catch(reject);
+        });
+    },
+
     /**
      * 添加子任务
      * @param dispatch

resources/assets/sass/pages/components/task-detail.scss

@@ -674,6 +674,24 @@
                                 }
                             }
 
+                            .related-remove {
+                                flex-shrink: 0;
+                                font-size: 14px;
+                                color: #c5c8ce;
+                                cursor: pointer;
+                                opacity: 0;
+                                transition: opacity 0.2s ease, color 0.2s ease;
+                                margin-left: 4px;
+
+                                &:hover {
+                                    color: #ed4014;
+                                }
+                            }
+
+                            &:hover .related-remove {
+                                opacity: 1;
+                            }
+
                             .ivu-tag {
                                 margin-left: 8px;
                             }