📦 NEW: usePipe support

[msaaddev]

This PR adds usePipe support in Langbase SDK.

Usage

import { usePipe } from 'langbase/react';

const {
	messages,
	input,
	handleInputChange,
	handleSubmit,
	isLoading,
	error,
	regenerate,
	stop,
	setMessages,
	threadId,
	sendMessage,
} = usePipe({
	stream: true,
	apiRoute: '/langbase/pipe/run-stream',
	onResponse: handleResponse,
	onFinish: handleFinish,
	onError: handleError,
});