feat: 企微回调服务基建（加解密+事件分发，默认关闭）

lib/wecom-callback-events.ts

@@ -0,0 +1,54 @@
+export type WecomCallbackFields = Record<string, string>;
+
+export type WecomCallbackEventResult = {
+  recognized: boolean;
+  action: string;
+  taskId: string;
+  btnKey: string;
+  operator: string;
+};
+
+export function parseWecomCallbackXml(xml: string): WecomCallbackFields {
+  const fields: WecomCallbackFields = {};
+  const source = String(xml ?? "");
+  const pattern =
+    /<([A-Za-z][A-Za-z0-9_]*)>(?:<!\[CDATA\[([\s\S]*?)\]\]>|([^<]*))<\/\1>/g;
+  let match: RegExpExecArray | null;
+  while ((match = pattern.exec(source)) !== null) {
+    const tag = match[1];
+    const value = match[2] ?? match[3] ?? "";
+    if (!(tag in fields)) fields[tag] = value.trim();
+  }
+  return fields;
+}
+
+export function extractWecomEncryptField(body: string): string {
+  const fields = parseWecomCallbackXml(body);
+  return fields.Encrypt ?? "";
+}
+
+export function handleWecomCallbackEvent(
+  fields: WecomCallbackFields,
+): WecomCallbackEventResult {
+  const event = fields.Event ?? "";
+  const taskId = fields.TaskId ?? "";
+  const btnKey = fields.BtnKey ?? "";
+  const operator = fields.FromUserName ?? "";
+
+  if (fields.MsgType === "event" && event === "template_card_event") {
+    if (btnKey === "mark_handled") {
+      console.info(
+        "[KOC LOOP] wecom card ack",
+        { taskId, operator },
+      );
+      return { recognized: true, action: "card_ack", taskId, btnKey, operator };
+    }
+    return { recognized: true, action: "ignored", taskId, btnKey, operator };
+  }
+
+  console.info("[KOC LOOP] wecom callback event ignored", {
+    msgType: fields.MsgType ?? "",
+    event,
+  });
+  return { recognized: false, action: "ignored", taskId, btnKey, operator };
+}