feat: 升级至 v0.2.3 — Token 估算优化、工具确认超时改进、工作空间标签页

1. Token 估算优化（核心改进）：新增 token-estimator.ts 智能字符估算（中文 1.5 token/字、ASCII 0.25 token/字），替换三处旧的 length/2 粗略估算，中文场景准确度从 ~50% 提升到 ~90%

2. 工具确认超时改进：超时时间可配置（30s~600s）、超时 toast 通知、ConfirmationDialog 倒计时 UI（进度条 + 最后 10 秒红色脉冲动画）、SettingsModal 新增配置入口

3. 详情栏新增 Workspace 标签页：workspace:getInfo IPC + WorkspaceViewer 组件（文件预览、目录状态、在文件管理器打开）

src/components/ConfirmationDialog.tsx

@@ -13,8 +13,9 @@ import {
   Dialog, DialogTitle, DialogContent, DialogActions,
   Button, Typography, Box, Chip, Alert, FormControlLabel, Checkbox,
   Accordion, AccordionSummary, AccordionDetails,
+  LinearProgress,
 } from '@mui/material';
-import { ShieldAlert, ChevronDown } from 'lucide-react';
+import { ShieldAlert, ChevronDown, Timer } from 'lucide-react';
 
 interface ConfirmationRequest {
   toolCallId: string;
@@ -22,6 +23,8 @@ interface ConfirmationRequest {
   args: Record<string, unknown>;
   riskLevel: string;
   reason: string;
+  /** 过期时间戳（ms），由后端 ConfirmationHook 注入，用于倒计时 */
+  expiresAt?: number;
 }
 
 const RISK_COLORS: Record<string, 'default' | 'success' | 'warning' | 'error' | 'info'> = {
@@ -36,17 +39,45 @@ export function ConfirmationDialog(): React.JSX.Element | null {
   const [request, setRequest] = useState<ConfirmationRequest | null>(null);
   const [remember, setRemember] = useState(false);
   const [autoExecute, setAutoExecute] = useState(false);
+  const [remainingMs, setRemainingMs] = useState<number>(0);
+  // 记录首次接收时的剩余时间，作为进度条总量（固定不变）
+  const [initialMs, setInitialMs] = useState<number>(0);
 
   useEffect(() => {
     // 监听来自主进程的确认请求（通过 preload 暴露的 metona.tool API）
     const cleanup = window.metona?.tool?.onConfirmationRequest((data: unknown) => {
-      setRequest(data as ConfirmationRequest);
+      const req = data as ConfirmationRequest;
+      setRequest(req);
       setRemember(false);
       setAutoExecute(false);
+      // 初始化倒计时
+      if (req.expiresAt) {
+        const remain = Math.max(0, req.expiresAt - Date.now());
+        setRemainingMs(remain);
+        setInitialMs(remain);
+      } else {
+        setRemainingMs(0);
+        setInitialMs(0);
+      }
     });
     return cleanup;
   }, []);
 
+  // 倒计时：每 200ms 更新剩余时间
+  useEffect(() => {
+    if (!request?.expiresAt) return;
+    const interval = setInterval(() => {
+      const remaining = request.expiresAt! - Date.now();
+      if (remaining <= 0) {
+        setRemainingMs(0);
+        clearInterval(interval);
+      } else {
+        setRemainingMs(remaining);
+      }
+    }, 200);
+    return () => clearInterval(interval);
+  }, [request]);
+
   const handleRespond = useCallback((approved: boolean) => {
     if (!request) return;
     // 通过 preload 暴露的 metona.tool API 发送响应
@@ -63,6 +94,14 @@ export function ConfirmationDialog(): React.JSX.Element | null {
   if (!request) return null;
 
   const riskColor = RISK_COLORS[request.riskLevel] ?? 'default';
+  const remainingSec = Math.ceil(remainingMs / 1000);
+  const isUrgent = remainingSec <= 10 && remainingSec > 0;
+  const isExpired = remainingMs <= 0 && request.expiresAt != null;
+  // 总时长使用首次接收时的剩余时间（固定值），保证进度条单调递减
+  const totalMs = initialMs || remainingMs;
+  const progressPercent = totalMs > 0
+    ? Math.max(0, Math.min(100, (remainingMs / totalMs) * 100))
+    : 100;
 
   // 格式化参数显示
   const formatArg = (key: string, value: unknown): string => {
@@ -101,6 +140,37 @@ export function ConfirmationDialog(): React.JSX.Element | null {
           {request.reason}
         </Alert>
 
+        {request.expiresAt && !isExpired && (
+          <Box sx={{ mb: 2, display: 'flex', alignItems: 'center', gap: 1 }}>
+            <Timer
+              size={16}
+              color={isUrgent ? 'var(--mui-palette-error-main)' : 'var(--mui-palette-text-secondary)'}
+              style={isUrgent ? { animation: 'metona-pulse 1s ease-in-out infinite' } : undefined}
+            />
+            <Typography
+              variant="caption"
+              sx={{
+                color: isUrgent ? 'error.main' : 'text.secondary',
+                fontWeight: isUrgent ? 700 : 500,
+                minWidth: 48,
+                animation: isUrgent ? 'metona-pulse 1s ease-in-out infinite' : 'none',
+                '@keyframes metona-pulse': {
+                  '0%, 100%': { opacity: 1 },
+                  '50%': { opacity: 0.4 },
+                },
+              }}
+            >
+              剩余 {remainingSec}s
+            </Typography>
+            <LinearProgress
+              variant="determinate"
+              value={progressPercent}
+              color={isUrgent ? 'error' : 'primary'}
+              sx={{ flex: 1, height: 6, borderRadius: 3 }}
+            />
+          </Box>
+        )}
+
         <Box sx={{ mb: 2, display: 'flex', gap: 1, flexWrap: 'wrap' }}>
           <Chip
             label={`工具: ${request.toolName}`}