xacmeobtainconfig类型
一站式配置：账户层 + 客户端层 + 续签层，全部借用视图，
typedef struct xacmeobtainconfig { const xacmeaccountconfig* pAccount; cstr sCaPem; struct xnetengine* pBorrowedEngine; int64 uTimeoutMs; const cstr* sPropagateResolvers; size_t iPropagateResolverCount; uint32 uPropagateTimeoutMs; int64 uIssueTimeoutMs; cstr sCertKeyPem; cstr sStoreRoot; int iRenewalDays; } xacmeobtainconfig;
xrtAcmeObtainConfigInit函数
全零初始化；指针字段为空表示未设置。
XRT_API void xrtAcmeObtainConfigInit(xacmeobtainconfig* pConfig)
xrtAcmeObtain函数
一次调用取得可用证书（链 + 配对私钥）：
XRT_API bool xrtAcmeObtain(const xacmeobtainconfig* pConfig, const xstrview* pDomains, size_t iDomainCount, const xacmednsprovider* pDns, xacmeissuegrant* pOut, bool* pbRenewed)