test: drop obsolete reply session placeholder

src/auto-reply/reply.session.test.ts

@@ -1,6 +0,0 @@
-import { describe, it } from "vitest";
-
-// Placeholder suite to keep vitest happy; legacy session reply coverage lives in other files.
-describe.skip("reply.session (legacy)", () => {
-  it("placeholder", () => {});
-});