eLabSDK2.Bootloader.HandlerInvoker

Wraps an add-on-registered callback id (returned by sdkFacade when an add-on passes a function as an SDK arg) into a host-callable (...args) => Promise<unknown>. The wrapper posts an invoke-handler message over the add-on's channel, awaits the matching result / error reply, and re-throws errors as plain Errors.

Auto-unwraps SDK arguments: if the host passes a wrapped handler stub ({ __addonHandler }) back into a callback's args (e.g. echoing an onClick handler reference), isHandlerStub recognises it and the iframe re-invokes that handler locally instead of round-tripping.

One invoker per AddonChannel; the RpcBroker holds them in a WeakMap keyed by channel.