refactor: unify typing callbacks

src/channels/typing.ts

@@ -0,0 +1,27 @@
+export type TypingCallbacks = {
+  onReplyStart: () => Promise<void>;
+  onIdle?: () => void;
+};
+
+export function createTypingCallbacks(params: {
+  start: () => Promise<void>;
+  stop?: () => Promise<void>;
+  onStartError: (err: unknown) => void;
+  onStopError?: (err: unknown) => void;
+}): TypingCallbacks {
+  const onReplyStart = async () => {
+    try {
+      await params.start();
+    } catch (err) {
+      params.onStartError(err);
+    }
+  };
+
+  const onIdle = params.stop
+    ? () => {
+        void params.stop().catch((err) => (params.onStopError ?? params.onStartError)(err));
+      }
+    : undefined;
+
+  return { onReplyStart, onIdle };
+}