feat: confirm creating missing session cwd

server.js

@@ -937,6 +937,58 @@ function getDefaultSessionCwd() {
     || path.resolve(process.cwd());
 }
 
+function resolveSessionCwd(candidate, options = {}) {
+  if (!candidate || !String(candidate).trim()) {
+    return { ok: true, path: getDefaultSessionCwd(), created: false };
+  }
+
+  const resolvedPath = path.resolve(String(candidate).trim());
+
+  try {
+    if (fs.existsSync(resolvedPath)) {
+      const realPath = fs.realpathSync(resolvedPath);
+      const stat = fs.statSync(realPath);
+      if (!stat.isDirectory()) {
+        return {
+          ok: false,
+          code: 'new_session_cwd_invalid',
+          resolvedPath,
+          message: '工作目录不是目录，请重新选择。',
+        };
+      }
+      return { ok: true, path: realPath, created: false };
+    }
+
+    if (!options.createMissing) {
+      return {
+        ok: false,
+        code: 'new_session_cwd_missing',
+        resolvedPath,
+        message: '工作目录不存在',
+      };
+    }
+
+    fs.mkdirSync(resolvedPath, { recursive: true });
+    const createdPath = normalizeExistingDirPath(resolvedPath);
+    if (!createdPath) {
+      return {
+        ok: false,
+        code: 'new_session_cwd_create_failed',
+        resolvedPath,
+        message: '目录已创建，但当前进程无法访问，请检查权限。',
+      };
+    }
+    return { ok: true, path: createdPath, created: true };
+  } catch (err) {
+    return {
+      ok: false,
+      code: options.createMissing ? 'new_session_cwd_create_failed' : 'new_session_cwd_invalid',
+      resolvedPath,
+      message: `${options.createMissing ? '创建工作目录失败' : '解析工作目录失败'}: ${err.message}`,
+    };
+  }
+}
+
 function collectRecentSessionCwds(limit = 12) {
   const results = [];
   const seen = new Set();
@@ -2564,10 +2616,16 @@ function handleNewSession(ws, msg) {
   const cwd = (msg && msg.cwd) ? String(msg.cwd) : null;
   const agent = normalizeAgent(msg?.agent);
   const requestedMode = ['default', 'plan', 'yolo'].includes(msg?.mode) ? msg.mode : 'yolo';
-  if (cwd && !normalizeExistingDirPath(cwd)) {
-    return wsSend(ws, { type: 'error', message: '工作目录不存在或不可访问，请重新选择。' });
+  const cwdResult = resolveSessionCwd(cwd, { createMissing: !!msg?.createCwd });
+  if (!cwdResult.ok) {
+    return wsSend(ws, {
+      type: 'error',
+      code: cwdResult.code,
+      cwd: cwdResult.resolvedPath || cwd || null,
+      message: cwdResult.message,
+    });
   }
-  const resolvedCwd = normalizeExistingDirPath(cwd) || getDefaultSessionCwd();
+  const resolvedCwd = cwdResult.path || getDefaultSessionCwd();
   const id = crypto.randomUUID();
   const session = {
     id,