feat: add WeChat MP channel support and enhance widget configuration

- Updated output path for generated enums to reflect new structure.
- Enhanced ChannelController to handle WeChat MP OAuth authorization and callback.
- Introduced WechatMPChannelConfig DTO for WeChat MP specific configurations.
- Modified WidgetConfigResponse to include channel type and external source.
- Added enums for WeChat MP channel type and external source.
- Implemented OAuth flow for WeChat MP, including state signing and verification.
- Updated frontend forms to accommodate WeChat MP configurations.
- Enhanced API interactions to support WeChat MP external ID and source.
- Updated generated enums to include WeChat MP external source.

web/lib/im-realtime.ts

@@ -19,7 +19,9 @@ export function createImRealtimeConnection() {
   const baseUrl = apiBaseUrl
     ? apiBaseUrl.replace(/^http/, "ws").replace(/\/$/, "")
     : createWebSocketBaseUrl()
-  const externalId = encodeURIComponent(getImVisitorId())
+  const resolvedExternalId = encodeURIComponent(
+    (config.externalId ?? "").trim() || getImVisitorId()
+  )
   const externalSource = encodeURIComponent(
     (config.externalSource ?? "web_chat").trim() || "web_chat"
   )
@@ -30,6 +32,6 @@ export function createImRealtimeConnection() {
       ? `&externalName=${encodeURIComponent(externalName)}`
       : ""
   return new WebSocket(
-    `${baseUrl}/api/ws/open?externalId=${externalId}&externalSource=${externalSource}&channelId=${channelId}${nameQuery}`
+    `${baseUrl}/api/ws/open?externalId=${resolvedExternalId}&externalSource=${externalSource}&channelId=${channelId}${nameQuery}`
   )
 }