feat(rcs): migrate all RCS APIs from rainyun-go-sdk

- 35 endpoints across 14 files, response structs split for reuse
- Reuse RcsRecord/Node/Plan/OsInfo/UsageData across list/detail/create
- Fix source bugs: {id} path placeholders, missing / in firewall pos path,
  missing body in ChargeRcsTrafic, resp vs &resp
- Add HTTPMethod_PATCH, common.BasicOperationResponse, VncConnectionInfo

apis/common/vnc.go

@@ -0,0 +1,19 @@
+package common
+
+import "strconv"
+
+type VncConnectionInfo struct {
+	Code int               `json:"code"`
+	Data VncConnectionData `json:"data"`
+}
+
+type VncConnectionData struct {
+	RequestURL  string `json:"RequestURL"`  // 空
+	RedirectURL string `json:"RedirectURL"` // 空
+	PVEAuth     string `json:"PVEAuth"`     // 空
+	VNCProxyURL string `json:"VNCProxyURL"` // PVE代理地址(连接地址)，里面会有一个unicode码(\u0026)(&),转码后就是可以直接在浏览器上使用的VNC连接地址
+}
+
+func GetVncConnectURL(v *VncConnectionInfo) (string, error) {
+	return strconv.Unquote(v.Data.VNCProxyURL)
+}