fix(HEL-243): 当前账号可点击返回，避免切换死路

当前账号行原先只显示对号、不可点击，单账号时只能关网页。现改为整行继续使用且不重新签发会话，并带回切换前的业务页。

Co-authored-by: Cursor <cursoragent@cursor.com>
Co-authored-by: multica-agent <github@multica.ai>

tests/test_login_portal.py

@@ -46,9 +46,22 @@ class LoginPortalContractTests(unittest.TestCase):
 
     def test_portal_keeps_account_switch_and_theme_hooks(self) -> None:
         self.assertIn("data-switch-id", LOGIN_JS)
+        self.assertIn("data-resume-id", LOGIN_JS)
         self.assertIn('data-login-action="manage"', LOGIN_JS)
         self.assertIn('data-login-action="add"', LOGIN_JS)
+        self.assertIn('data-login-action="resume"', LOGIN_JS)
+        self.assertIn("继续使用", LOGIN_JS)
+        self.assertIn("返回复盘", LOGIN_JS)
+        self.assertIn("/api/auth/me", LOGIN_JS)
         self.assertIn("xiaobaiTheme", LOGIN_JS)
         self.assertNotIn("内网个人版", LOGIN)
         self.assertNotIn("192.168.200.11", LOGIN)
         self.assertNotIn("/api/heaven", LOGIN_JS)
+
+    def test_current_account_row_stays_clickable_without_reswitching(self) -> None:
+        self.assertIn("resumeCurrentAccount", LOGIN_JS)
+        self.assertIn("当前会话已失效，请重新登录", LOGIN_JS)
+        self.assertNotIn("!managing && !current ? \"is-switchable\"", LOGIN_JS)
+        session = (ROOT / "frontend" / "shared" / "session.js").read_text(encoding="utf-8")
+        self.assertIn('params.set("next", next)', session)
+        self.assertIn(".login-account-action", AUTH)