modify: auth插件拆分，将token签发部分交给网关

workers/auth_oauth/phone_login.toml

@@ -0,0 +1,12 @@
+[POST]
+summary = "手机验证码登录：校验验证码并签发平台 token"
+docstring = "校验一次性验证码后，按手机号绑定关系 find-or-create 账号，签发与内置登录同契约的平台 token。"
+auth_required = false
+cacheable = false
+params = ["phone: str", "code: str"]
+
+[POST.response_model]
+result = { type = "str", required = true }
+token = { type = "str", required = true }
+message = { type = "str", required = true }
+timestamp = { type = "float", required = false }