fix(连接): 默认校验 T+ 证书并限制开发端口

T+ 连接默认校验服务器证书，隔离开发回退须显式配置。
MySQL 与 Redis 的开发端口仅绑定本机回环地址。

backend/tests/unit/test_tplus_config.py

@@ -34,14 +34,14 @@ def test_T加未启用时读取器不建立连接() -> None:
     assert settings.t_plus_enabled is False
 
 
-def test_T加默认加密且允许显式隔离环境回退(monkeypatch) -> None:
+def test_T加默认加密并默认校验服务器证书(monkeypatch) -> None:
     monkeypatch.delenv("T_PLUS_ENCRYPT", raising=False)
     monkeypatch.delenv("T_PLUS_TRUST_SERVER_CERTIFICATE", raising=False)
     assert _settings().t_plus_database_url.query["Encrypt"] == "yes"
-    assert _settings().t_plus_database_url.query["TrustServerCertificate"] == "yes"
-    url = _settings(t_plus_encrypt=False, t_plus_trust_server_certificate=False).t_plus_database_url
+    assert _settings().t_plus_database_url.query["TrustServerCertificate"] == "no"
+    url = _settings(t_plus_encrypt=False, t_plus_trust_server_certificate=True).t_plus_database_url
     assert url.query["Encrypt"] == "no"
-    assert url.query["TrustServerCertificate"] == "no"
+    assert url.query["TrustServerCertificate"] == "yes"
 
 
 @pytest.mark.parametrize("value", ["a;b", "a}b", "{prefix", "中文;UID=other}x"])