dispatch: typed handlers, respond/defer/error, automatic ErrorResponse, watchdog

src/dispatcher.ts routes a directive to capability.on(name | "*"), device.onDirective() or
device.onReportState(), with the payload checked by the descriptor of the interface. The
DirectiveContext answers with respond/report/defer/error; respond() and report() start from
device.state(). A handler or 1.x listener that throws or rejects is answered with INTERNAL_ERROR
(an AlexaError with itself) and reported through "error", never as an unhandled rejection.
Undeclared interface, unknown directive, AdjustMode on an unordered mode and a missing handler
get INVALID_DIRECTIVE, a bad payload INVALID_VALUE; a device with an "Event" or "ReportState"
listener keeps the answer to itself. Every answer passes the dispatcher: the first one per
correlationToken is published, a second is refused. No answer within answerWithinMs (6500,
0 = off, unref'd timer) sends INTERNAL_ERROR and emits "unanswered". A messageId that arrived
in the last 60 s is dropped. New: "unknownEndpoint", options answerUnknownEndpoints, publisher,
timers, and bridge.receive() to run a bridge without a broker. 168 tests pass (18 new).

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

src/index.ts

@@ -39,6 +39,9 @@ export * as topics from "./topics.js";
 export { MemoryPublisher } from "./transport.js";
 export type { Publisher, PublishResult } from "./transport.js";
 
+// Directives: what a handler is given
+export type { DirectiveContext, DirectiveHandler, Fill, RawDirective, Timers } from "./dispatcher.js";
+
 // 1.x
 export { AlexaInterface } from "./compat/AlexaInterface.js";
 export type { SupportedMode } from "./compat/AlexaInterface.js";