test(auto-reply): install channel metadata for group prompt cases (#108113)

AGENTS.md

@@ -126,7 +126,7 @@ Skills own workflows; root owns hard policy and routing.
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-- Formatting: `oxfmt`, not Prettier. Use repo wrappers (`pnpm format:*`, `scripts/run-oxlint.mjs`; full `pnpm lint:*` only when scope requires).
+- Formatting: `oxfmt`, not Prettier. Write paths with `pnpm format <paths>`; no `format:write` script. Checks use repo wrappers (`pnpm format:*`, `scripts/run-oxlint.mjs`; full `pnpm lint:*` only when scope requires).
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src/auto-reply/reply.triggers.group-intro-prompts.cases.ts

@@ -1,6 +1,8 @@
 /** Reusable group-intro prompt assertions shared by auto-reply trigger tests. */
-import { describe, expect, it } from "vitest";
+import { afterEach, beforeEach, describe, expect, it } from "vitest";
 import { makeCfg } from "../../test/helpers/auto-reply/trigger-handling-test-harness.js";
+import { resetPluginRuntimeStateForTest, setActivePluginRegistry } from "../plugins/runtime.js";
+import { createChannelTestPluginBase, createTestRegistry } from "../test-utils/channel-plugins.js";
 import { buildGroupChatContext, buildGroupIntro } from "./reply/groups.js";
 
 type GetReplyFromConfig = typeof import("./reply.js").getReplyFromConfig;
@@ -8,6 +10,25 @@ type InboundMessage = Parameters<GetReplyFromConfig>[0];
 
 export function registerGroupIntroPromptCases(): void {
   describe("group intro prompts", () => {
+    beforeEach(() => {
+      resetPluginRuntimeStateForTest();
+      setActivePluginRegistry(
+        createTestRegistry([
+          {
+            pluginId: "telegram",
+            source: "test",
+            plugin: {
+              ...createChannelTestPluginBase({ id: "telegram" }),
+              messaging: { defaultMarkdownTableMode: "block" },
+            },
+          },
+        ]),
+      );
+    });
+    afterEach(() => {
+      resetPluginRuntimeStateForTest();
+    });
+
     type GroupIntroCase = {
       name: string;
       message: InboundMessage;