feat(web): add WeCom QR binding flow to channel settings (#1994)

- add backend WeCom QR flow endpoints and in-memory flow state management
- add frontend WeCom binding UI with QR polling and channel enable toggle
- update channel config behavior and i18n strings for WeCom and WeChat
- apply minor formatting cleanup in model-related components

web/frontend/src/api/channels.ts

@@ -72,6 +72,14 @@ export interface WeixinFlowResponse {
   error?: string
 }
 
+export interface WecomFlowResponse {
+  flow_id: string
+  status: "wait" | "scaned" | "confirmed" | "expired" | "error"
+  qr_data_uri?: string
+  bot_id?: string
+  error?: string
+}
+
 export async function startWeixinFlow(): Promise<WeixinFlowResponse> {
   return request<WeixinFlowResponse>("/api/weixin/flows", { method: "POST" })
 }
@@ -84,4 +92,16 @@ export async function pollWeixinFlow(
   )
 }
 
+export async function startWecomFlow(): Promise<WecomFlowResponse> {
+  return request<WecomFlowResponse>("/api/wecom/flows", { method: "POST" })
+}
+
+export async function pollWecomFlow(
+  flowID: string,
+): Promise<WecomFlowResponse> {
+  return request<WecomFlowResponse>(
+    `/api/wecom/flows/${encodeURIComponent(flowID)}`,
+  )
+}
+
 export type { ChannelsCatalogResponse, ConfigActionResponse }