feat: async support for process functions

[oseoin]

Proposed changes

Adds support for running process_input and process_response as async. Have performed performance tests with both options and have not seen any meaningful difference between the two. pyright seems to be happy with the implementation.

Checklist

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• I have written my commit messages in the Conventional Commits format.
• I have read the CONTRIBUTING doc
• I have added tests (when possible) that prove my fix is effective or that my feature works
• I have checked that all unit tests pass after adding my changes
• I have updated necessary documentation
• I have rebased my branch onto main
• I will ensure my PR is targeting the main branch and pulling from my branch from my own fork

[andrey-zelenkov]

nit: can suggest to unwrap decorators for a little bit more safety

Suggested change

	if is_process_overridden and inspect.iscoroutinefunction(cls.process):
	if is_process_overridden and inspect.iscoroutinefunction(inspect.unwrap(cls.process)):

[andrey-zelenkov]

Suggested change

	async def test_async_message(self):
	prompt = TEST_REQ_INPUT.model_dump_json()
	metadata = {"key": "value"}
	request = fake_multipart_request(
	prompt=prompt,
	metadata=metadata,
	parameters={"modify": True, "annotate": True},
	)
	class AsyncInputProcessor(Processor):
	def __init__(self):
	super().__init__(
	name="async-input-processor",
	namespace="fake",
	signature=INPUT_ONLY_SIGNATURE,
	version="v1",
	)
	async def process_input(self, prompt, metadata, parameters, request) -> Result:
	prompt.messages.append(Message(content="Test message"))
	return Result(modified_prompt=prompt)
	processor = AsyncInputProcessor()
	response = await processor.handle_request(request)
	self.assertStatusCodeEqual(response, HTTP_200_OK)
	content = await self.buffer_response(response)
	multipart = MultipartDecoderHelper(
	content=content, content_type=response.headers["Content-Type"]
	)
	self.assertTrue(
	multipart.has_prompt(),
	"prompt should be in the response",
	)
	multipart_prompt = multipart.prompt
	assert "Test message" in multipart_prompt.content