feat: 建立 SAM2 标注闭环基线

- 打通工作区真实标注闭环：支持手工多边形、矩形、圆形、点区域和线段生成 mask，并可保存、回显、更新和删除后端 annotation。

- 增强 polygon 编辑器：支持顶点拖动、顶点删除、边中点插入、多 polygon 子区域选择编辑，以及区域合并和区域去除。

- 接入 GT mask 导入：后端支持二值/多类别 mask 拆分、contour 转 polygon、distance transform seed point，前端支持导入、回显和 seed point 拖动编辑。

- 完善导出能力：COCO JSON 导出对齐前端，PNG mask ZIP 同时包含单标注 mask、按 zIndex 融合的 semantic_frame 和 semantic_classes.json。

- 打通异步任务管理：新增任务取消、重试、失败详情接口与 Dashboard 控件，worker 支持取消状态检查并通过 Redis/WebSocket 推送 cancelled 事件。

- 对接 Dashboard 后端数据：概览统计、解析队列和实时流转记录从 FastAPI 聚合接口与 WebSocket 更新。

- 增强 AI 推理参数：前端发送 crop_to_prompt、auto_filter_background 和 min_score，后端支持点/框 prompt 局部裁剪推理、结果回映射和负向点/低分过滤。

- 接入 SAM3 基础设施：新增独立 Python 3.12 sam3 环境安装脚本、外部 worker helper、后端桥接和真实 Python/CUDA/包/HF checkpoint access 状态检测。

- 保留 SAM3 授权边界：当前官方 facebook/sam3 gated 权重未授权时状态接口会返回不可用，不伪装成可推理。

- 增强前端状态管理：新增 mask undo/redo 历史栈、AI 模型选择状态、保存状态 dirty/draft/saved 流转和项目状态归一化。

- 更新前端 API 封装：补充 annotation CRUD、GT mask import、mask ZIP export、task cancel/retry/detail、AI runtime status 和 prediction options。

- 更新 UI 控件：ToolsPalette、AISegmentation、VideoWorkspace 和 CanvasArea 接入真实操作、导入导出、撤销重做、任务控制和模型状态。

- 新增 polygon-clipping 依赖，用于前端区域 union/difference 几何运算。

- 完善后端 schemas/status/progress：补充 AI 模型外部状态字段、任务 cancelled 状态和进度事件 payload。

- 补充测试覆盖：新增后端任务控制、SAM3 桥接、GT mask、导出融合、AI options 测试；补充前端 Canvas、Dashboard、VideoWorkspace、ToolsPalette、API 和 store 测试。

- 更新 README、AGENTS 和 doc 文档：冻结当前需求/设计/测试计划，标注真实功能、剩余 Mock、SAM3 授权边界和后续实施顺序。

src/components/Dashboard.tsx

@@ -1,8 +1,17 @@
 import React, { useState, useEffect } from 'react';
-import { Activity, Clock, Folders, CheckCircle2, Loader2 } from 'lucide-react';
+import { Activity, AlertTriangle, Clock, Folders, CheckCircle2, Info, Loader2, RotateCcw, XCircle } from 'lucide-react';
 import { progressWS, type ProgressMessage } from '../lib/websocket';
 import { cn } from '../lib/utils';
-import { getDashboardOverview, type DashboardActivity, type DashboardOverview, type DashboardTask } from '../lib/api';
+import {
+  cancelTask,
+  getDashboardOverview,
+  getTask,
+  retryTask,
+  type DashboardActivity,
+  type DashboardOverview,
+  type DashboardTask,
+  type ProcessingTask,
+} from '../lib/api';
 
 const emptySummary: DashboardOverview['summary'] = {
   project_count: 0,
@@ -20,6 +29,29 @@ export function Dashboard() {
   const [activityLog, setActivityLog] = useState<DashboardActivity[]>([]);
   const [isLoading, setIsLoading] = useState(true);
   const [loadError, setLoadError] = useState('');
+  const [selectedTask, setSelectedTask] = useState<ProcessingTask | null>(null);
+  const [taskActionMessage, setTaskActionMessage] = useState('');
+  const [busyTaskId, setBusyTaskId] = useState<string | null>(null);
+
+  const taskFromProcessingTask = (task: ProcessingTask, name = `任务 ${task.id}`): DashboardTask => ({
+    id: `task-${task.id}`,
+    task_id: task.id,
+    project_id: task.project_id ?? 0,
+    name,
+    progress: task.progress,
+    status: task.message || task.status,
+    raw_status: task.status,
+    error: task.error,
+    frame_count: Number(task.result?.frames_extracted || 0),
+    updated_at: task.updated_at,
+  });
+
+  const prependActivity = (message: string, project = '系统') => {
+    setActivityLog((prev) => [
+      { id: `task-action-${Date.now()}`, kind: 'task', time: new Date().toISOString(), message, project },
+      ...prev.slice(0, 9),
+    ]);
+  };
 
   useEffect(() => {
     let cancelled = false;
@@ -90,6 +122,8 @@ export function Dashboard() {
               name: taskTitle(data),
               progress: data.progress ?? 0,
               status: data.status ?? '处理中',
+              raw_status: 'running',
+              error: data.error,
               frame_count: 0,
               updated_at: new Date().toISOString(),
             },
@@ -100,7 +134,7 @@ export function Dashboard() {
       if (data.type === 'complete' && data.taskId) {
         setTasks((prev) =>
           prev.map((t) =>
-            t.id === data.taskId ? { ...t, progress: 100, status: '已完成' } : t
+            t.id === data.taskId ? { ...t, progress: 100, status: '已完成', raw_status: 'success' } : t
           )
         );
         setActivityLog((prev) => [
@@ -109,10 +143,26 @@ export function Dashboard() {
         ]);
       }
 
+      if (data.type === 'cancelled' && data.taskId) {
+        setTasks((prev) =>
+          prev.map((t) =>
+            t.id === data.taskId
+              ? { ...t, progress: 100, status: data.message || '任务已取消', raw_status: 'cancelled', error: data.error }
+              : t
+          )
+        );
+        setActivityLog((prev) => [
+          { id: `ws-cancelled-${Date.now()}`, kind: 'websocket', time: new Date().toISOString(), message: data.message || `任务已取消: ${taskTitle(data)}`, project: data.projectName || '系统' },
+          ...prev.slice(0, 9),
+        ]);
+      }
+
       if (data.type === 'error' && data.taskId) {
         setTasks((prev) =>
           prev.map((t) =>
-            t.id === data.taskId ? { ...t, progress: data.progress ?? t.progress, status: `错误: ${data.error || data.message || '未知错误'}` } : t
+            t.id === data.taskId
+              ? { ...t, progress: data.progress ?? t.progress, status: `错误: ${data.error || data.message || '未知错误'}`, raw_status: 'failed', error: data.error }
+              : t
           )
         );
         setActivityLog((prev) => [
@@ -160,6 +210,65 @@ export function Dashboard() {
     });
   }
 
+  const taskRawStatus = (task: DashboardTask): string => task.raw_status || (
+    task.status.includes('取消') ? 'cancelled'
+      : task.status.includes('失败') || task.status.includes('错误') ? 'failed'
+        : task.progress >= 100 ? 'success'
+          : 'running'
+  );
+
+  const canCancel = (task: DashboardTask): boolean => ['queued', 'running'].includes(taskRawStatus(task)) && Boolean(task.task_id);
+  const canRetry = (task: DashboardTask): boolean => ['failed', 'cancelled'].includes(taskRawStatus(task)) && Boolean(task.task_id);
+
+  const handleCancelTask = async (task: DashboardTask) => {
+    if (!task.task_id) return;
+    setBusyTaskId(task.id);
+    setTaskActionMessage('');
+    try {
+      const updated = await cancelTask(task.task_id);
+      setTasks((prev) => prev.map((item) => (
+        item.id === task.id ? taskFromProcessingTask(updated, task.name) : item
+      )));
+      prependActivity(`任务已取消 #${updated.id}`, task.name);
+    } catch (err) {
+      console.error('Cancel task failed:', err);
+      setTaskActionMessage('任务取消失败，请检查后端服务');
+    } finally {
+      setBusyTaskId(null);
+    }
+  };
+
+  const handleRetryTask = async (task: DashboardTask) => {
+    if (!task.task_id) return;
+    setBusyTaskId(task.id);
+    setTaskActionMessage('');
+    try {
+      const retried = await retryTask(task.task_id);
+      const dashboardTask = taskFromProcessingTask(retried, task.name);
+      setTasks((prev) => [dashboardTask, ...prev.filter((item) => item.id !== dashboardTask.id)]);
+      prependActivity(`重试任务已入队 #${retried.id}`, task.name);
+    } catch (err) {
+      console.error('Retry task failed:', err);
+      setTaskActionMessage('任务重试失败，请检查后端服务');
+    } finally {
+      setBusyTaskId(null);
+    }
+  };
+
+  const handleOpenTaskDetail = async (task: DashboardTask) => {
+    if (!task.task_id) return;
+    setBusyTaskId(task.id);
+    setTaskActionMessage('');
+    try {
+      setSelectedTask(await getTask(task.task_id));
+    } catch (err) {
+      console.error('Load task detail failed:', err);
+      setTaskActionMessage('失败详情加载失败');
+    } finally {
+      setBusyTaskId(null);
+    }
+  };
+
   return (
     <div className="p-8 w-full h-full overflow-y-auto bg-[#0a0a0a]">
       <header className="mb-8">
@@ -177,6 +286,7 @@ export function Dashboard() {
         </div>
         <p className="text-gray-400 text-sm mt-1">系统全局数据吞吐状态与所有接入项目进度实时洞察驾驶舱。</p>
         {loadError && <p className="text-red-400 text-xs mt-2">{loadError}</p>}
+        {taskActionMessage && <p className="text-amber-400 text-xs mt-2">{taskActionMessage}</p>}
       </header>
 
       <div className="grid grid-cols-1 md:grid-cols-2 lg:grid-cols-4 gap-4 mb-8">
@@ -213,16 +323,47 @@ export function Dashboard() {
                     <div className="h-full bg-gradient-to-r from-cyan-600 to-cyan-400 rounded-full transition-all duration-500" style={{ width: `${task.progress}%` }} />
                   </div>
                   <div className="text-xs text-gray-500 flex items-center gap-2">
-                    {task.status === '已完成' || task.progress >= 100 ? (
+                    {taskRawStatus(task) === 'success' || task.status === '已完成' ? (
                       <CheckCircle2 size={12} className="text-emerald-400" />
-                    ) : task.status.includes('错误') ? (
-                      <span className="text-red-400">●</span>
+                    ) : taskRawStatus(task) === 'failed' ? (
+                      <AlertTriangle size={12} className="text-red-400" />
+                    ) : taskRawStatus(task) === 'cancelled' ? (
+                      <XCircle size={12} className="text-amber-400" />
                     ) : (
                       <Loader2 size={12} className="text-cyan-400 animate-spin" />
                     )}
                     {task.status}
                     <span className="text-gray-600">帧: {task.frame_count}</span>
                   </div>
+                  <div className="mt-3 flex flex-wrap items-center gap-2">
+                    {canCancel(task) && (
+                      <button
+                        onClick={() => handleCancelTask(task)}
+                        disabled={busyTaskId === task.id}
+                        className="inline-flex items-center gap-1 rounded border border-red-500/20 bg-red-500/10 px-2 py-1 text-[11px] text-red-300 hover:bg-red-500/20 disabled:opacity-40 disabled:cursor-not-allowed"
+                      >
+                        <XCircle size={12} /> 取消
+                      </button>
+                    )}
+                    {canRetry(task) && (
+                      <button
+                        onClick={() => handleRetryTask(task)}
+                        disabled={busyTaskId === task.id}
+                        className="inline-flex items-center gap-1 rounded border border-cyan-500/20 bg-cyan-500/10 px-2 py-1 text-[11px] text-cyan-300 hover:bg-cyan-500/20 disabled:opacity-40 disabled:cursor-not-allowed"
+                      >
+                        <RotateCcw size={12} /> 重试
+                      </button>
+                    )}
+                    {task.task_id && (
+                      <button
+                        onClick={() => handleOpenTaskDetail(task)}
+                        disabled={busyTaskId === task.id}
+                        className="inline-flex items-center gap-1 rounded border border-white/10 bg-white/5 px-2 py-1 text-[11px] text-gray-300 hover:bg-white/10 disabled:opacity-40 disabled:cursor-not-allowed"
+                      >
+                        <Info size={12} /> 详情
+                      </button>
+                    )}
+                  </div>
                 </div>
               ))}
               {!isLoading && tasks.length === 0 && (
@@ -253,6 +394,46 @@ export function Dashboard() {
            </div>
         </div>
       </div>
+
+      {selectedTask && (
+        <div className="fixed inset-0 z-50 flex items-center justify-center bg-black/70 px-4">
+          <div className="w-full max-w-2xl rounded-lg border border-white/10 bg-[#111] p-5 shadow-2xl">
+            <div className="flex items-center justify-between gap-3 border-b border-white/10 pb-3">
+              <div>
+                <h3 className="text-sm font-semibold text-white">任务详情 #{selectedTask.id}</h3>
+                <p className="mt-1 text-xs text-gray-500">{selectedTask.message || selectedTask.status}</p>
+              </div>
+              <button
+                onClick={() => setSelectedTask(null)}
+                className="rounded border border-white/10 bg-white/5 px-2 py-1 text-xs text-gray-300 hover:bg-white/10"
+              >
+                关闭
+              </button>
+            </div>
+            <div className="mt-4 grid grid-cols-2 gap-3 text-xs text-gray-400">
+              <div>状态: <span className="text-gray-200">{selectedTask.status}</span></div>
+              <div>进度: <span className="text-gray-200">{selectedTask.progress}%</span></div>
+              <div>项目 ID: <span className="text-gray-200">{selectedTask.project_id ?? '-'}</span></div>
+              <div>Celery ID: <span className="text-gray-200">{selectedTask.celery_task_id || '-'}</span></div>
+              <div>创建: <span className="text-gray-200">{selectedTask.created_at}</span></div>
+              <div>结束: <span className="text-gray-200">{selectedTask.finished_at || '-'}</span></div>
+            </div>
+            {selectedTask.error && (
+              <div className="mt-4 rounded border border-red-500/20 bg-red-500/10 p-3 text-xs text-red-200">
+                {selectedTask.error}
+              </div>
+            )}
+            <div className="mt-4 grid gap-3 md:grid-cols-2">
+              <pre className="max-h-48 overflow-auto rounded border border-white/10 bg-[#0a0a0a] p-3 text-[11px] text-gray-300">
+                {JSON.stringify(selectedTask.payload || {}, null, 2)}
+              </pre>
+              <pre className="max-h-48 overflow-auto rounded border border-white/10 bg-[#0a0a0a] p-3 text-[11px] text-gray-300">
+                {JSON.stringify(selectedTask.result || {}, null, 2)}
+              </pre>
+            </div>
+          </div>
+        </div>
+      )}
     </div>
   );
 }