feat(discord): add set-presence action for bot activity and status

Bridge the agent tools layer to the Discord gateway WebSocket via a new
gateway registry, allowing agents to set the bot's activity and online
status. Supports playing, streaming, listening, watching, custom, and
competing activity types. Custom type uses activityState as the sidebar
text; other types show activityName in the sidebar and activityState in
the flyout. Opt-in via channels.discord.actions.presence (default false).

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/agents/tools/discord-actions-presence.test.ts

@@ -0,0 +1,204 @@
+import type { GatewayPlugin } from "@buape/carbon/gateway";
+import { beforeEach, describe, expect, it, vi } from "vitest";
+import type { DiscordActionConfig } from "../../config/config.js";
+import type { ActionGate } from "./common.js";
+import { clearGateways, registerGateway } from "../../discord/monitor/gateway-registry.js";
+import { handleDiscordPresenceAction } from "./discord-actions-presence.js";
+
+const mockUpdatePresence = vi.fn();
+
+function createMockGateway(connected = true): GatewayPlugin {
+  return { isConnected: connected, updatePresence: mockUpdatePresence } as unknown as GatewayPlugin;
+}
+
+const presenceEnabled: ActionGate<DiscordActionConfig> = (key) => key === "presence";
+const presenceDisabled: ActionGate<DiscordActionConfig> = () => false;
+
+describe("handleDiscordPresenceAction", () => {
+  beforeEach(() => {
+    mockUpdatePresence.mockClear();
+    clearGateways();
+    registerGateway(undefined, createMockGateway());
+  });
+
+  it("sets playing activity", async () => {
+    const result = await handleDiscordPresenceAction(
+      "setPresence",
+      { activityType: "playing", activityName: "with fire", status: "online" },
+      presenceEnabled,
+    );
+    expect(mockUpdatePresence).toHaveBeenCalledWith({
+      since: null,
+      activities: [{ name: "with fire", type: 0 }],
+      status: "online",
+      afk: false,
+    });
+    const payload = JSON.parse(result.content[0].text ?? "");
+    expect(payload.ok).toBe(true);
+    expect(payload.activities[0]).toEqual({ type: 0, name: "with fire" });
+  });
+
+  it("sets streaming activity with optional URL", async () => {
+    await handleDiscordPresenceAction(
+      "setPresence",
+      {
+        activityType: "streaming",
+        activityName: "My Stream",
+        activityUrl: "https://twitch.tv/example",
+      },
+      presenceEnabled,
+    );
+    expect(mockUpdatePresence).toHaveBeenCalledWith({
+      since: null,
+      activities: [{ name: "My Stream", type: 1, url: "https://twitch.tv/example" }],
+      status: "online",
+      afk: false,
+    });
+  });
+
+  it("allows streaming without URL", async () => {
+    await handleDiscordPresenceAction(
+      "setPresence",
+      { activityType: "streaming", activityName: "My Stream" },
+      presenceEnabled,
+    );
+    expect(mockUpdatePresence).toHaveBeenCalledWith({
+      since: null,
+      activities: [{ name: "My Stream", type: 1 }],
+      status: "online",
+      afk: false,
+    });
+  });
+
+  it("sets listening activity", async () => {
+    await handleDiscordPresenceAction(
+      "setPresence",
+      { activityType: "listening", activityName: "Spotify" },
+      presenceEnabled,
+    );
+    expect(mockUpdatePresence).toHaveBeenCalledWith(
+      expect.objectContaining({
+        activities: [{ name: "Spotify", type: 2 }],
+      }),
+    );
+  });
+
+  it("sets watching activity", async () => {
+    await handleDiscordPresenceAction(
+      "setPresence",
+      { activityType: "watching", activityName: "you" },
+      presenceEnabled,
+    );
+    expect(mockUpdatePresence).toHaveBeenCalledWith(
+      expect.objectContaining({
+        activities: [{ name: "you", type: 3 }],
+      }),
+    );
+  });
+
+  it("sets custom activity using state", async () => {
+    await handleDiscordPresenceAction(
+      "setPresence",
+      { activityType: "custom", activityState: "Vibing" },
+      presenceEnabled,
+    );
+    expect(mockUpdatePresence).toHaveBeenCalledWith({
+      since: null,
+      activities: [{ name: "", type: 4, state: "Vibing" }],
+      status: "online",
+      afk: false,
+    });
+  });
+
+  it("includes activityState", async () => {
+    await handleDiscordPresenceAction(
+      "setPresence",
+      { activityType: "playing", activityName: "My Game", activityState: "In the lobby" },
+      presenceEnabled,
+    );
+    expect(mockUpdatePresence).toHaveBeenCalledWith({
+      since: null,
+      activities: [{ name: "My Game", type: 0, state: "In the lobby" }],
+      status: "online",
+      afk: false,
+    });
+  });
+
+  it("sets status-only without activity", async () => {
+    await handleDiscordPresenceAction("setPresence", { status: "idle" }, presenceEnabled);
+    expect(mockUpdatePresence).toHaveBeenCalledWith({
+      since: null,
+      activities: [],
+      status: "idle",
+      afk: false,
+    });
+  });
+
+  it("defaults status to online", async () => {
+    await handleDiscordPresenceAction(
+      "setPresence",
+      { activityType: "playing", activityName: "test" },
+      presenceEnabled,
+    );
+    expect(mockUpdatePresence).toHaveBeenCalledWith(expect.objectContaining({ status: "online" }));
+  });
+
+  it("rejects invalid status", async () => {
+    await expect(
+      handleDiscordPresenceAction("setPresence", { status: "offline" }, presenceEnabled),
+    ).rejects.toThrow(/Invalid status/);
+  });
+
+  it("rejects invalid activity type", async () => {
+    await expect(
+      handleDiscordPresenceAction("setPresence", { activityType: "invalid" }, presenceEnabled),
+    ).rejects.toThrow(/Invalid activityType/);
+  });
+
+  it("respects presence gating", async () => {
+    await expect(
+      handleDiscordPresenceAction("setPresence", { status: "online" }, presenceDisabled),
+    ).rejects.toThrow(/disabled/);
+  });
+
+  it("errors when gateway is not registered", async () => {
+    clearGateways();
+    await expect(
+      handleDiscordPresenceAction("setPresence", { status: "dnd" }, presenceEnabled),
+    ).rejects.toThrow(/not available/);
+  });
+
+  it("errors when gateway is not connected", async () => {
+    clearGateways();
+    registerGateway(undefined, createMockGateway(false));
+    await expect(
+      handleDiscordPresenceAction("setPresence", { status: "dnd" }, presenceEnabled),
+    ).rejects.toThrow(/not connected/);
+  });
+
+  it("uses accountId to resolve gateway", async () => {
+    const accountGateway = createMockGateway();
+    registerGateway("my-account", accountGateway);
+    await handleDiscordPresenceAction(
+      "setPresence",
+      { accountId: "my-account", activityType: "playing", activityName: "test" },
+      presenceEnabled,
+    );
+    expect(mockUpdatePresence).toHaveBeenCalled();
+  });
+
+  it("defaults activity name to empty string when only type is provided", async () => {
+    await handleDiscordPresenceAction("setPresence", { activityType: "playing" }, presenceEnabled);
+    expect(mockUpdatePresence).toHaveBeenCalledWith(
+      expect.objectContaining({
+        activities: [{ name: "", type: 0 }],
+      }),
+    );
+  });
+
+  it("rejects unknown presence actions", async () => {
+    await expect(handleDiscordPresenceAction("unknownAction", {}, presenceEnabled)).rejects.toThrow(
+      /Unknown presence action/,
+    );
+  });
+});