feat(agents): add warm transfer task

.changeset/agent-activity-tool-choice-als-leak.md

@@ -0,0 +1,5 @@
+---
+'@livekit/agents': patch
+---
+
+Fix `AgentActivity.generateReply` defaulting `toolChoice` to `'none'` on a child `AgentSession` spawned inside a tool. The previous check relied on `AsyncLocalStorage`, which leaks the parent function-call context into the child session and caused the framework to drop legitimate tool calls emitted by the child agent (e.g. the supervisor's `connect_to_caller` invocation in `WarmTransferTask`). The check now uses per-task info, matching the Python implementation.

.changeset/warm-transfer-task.md

@@ -0,0 +1,5 @@
+---
+'@livekit/agents': minor
+---
+
+Add beta WarmTransferTask workflow for SIP-based human handoffs.

agents/src/beta/index.ts

@@ -6,6 +6,9 @@ export {
   type TaskCompletedEvent,
   type TaskGroupOptions,
   type TaskGroupResult,
+  WarmTransferTask,
   type InstructionParts,
+  type WarmTransferResult,
+  type WarmTransferTaskOptions,
 } from './workflows/index.js';
 export { Instructions } from '../llm/index.js';

agents/src/beta/workflows/index.ts

@@ -7,4 +7,9 @@ export {
   type TaskGroupOptions,
   type TaskGroupResult,
 } from './task_group.js';
+export {
+  WarmTransferTask,
+  type WarmTransferResult,
+  type WarmTransferTaskOptions,
+} from './warm_transfer.js';
 export type { InstructionParts } from './utils.js';