Add HTTP retry handling into task SDK api.client

[jscheffl]

closes: #44355

Add HTTP retry handling to Task SDK.

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

Comments suppressed due to low confidence (1)

task_sdk/tests/api/test_client.py:101

• There is an extra single quote in the mounts dictionary key. It should be mounts={'http://': httpx.MockTransport(mock_handle_request)}.

mounts={'http://': httpx.MockTransport(mock_handle_request)},

[shubhamraj-git]

Overall looks good, some optimisations.

[shubhamraj-git]

Two things here:

1. Currently, the API_RETRIES, API_RETRY_WAIT_MIN, and API_RETRY_WAIT_MAX are directly cast to integers. This can raise a ValueError if the environment variables are not set correctly. Can we add validation or some fallback defaults (In case of error, if we don't want to fail)?
2. Let's also have a check, API_RETRY_WAIT_MIN < API_RETRY_WAIT_MAX and raise alarm if not ?

[shubhamraj-git]

The section of code has been duplicated multiple times. Should we consider getting them out?

@pytest.fixture
def mock_client():
    """Helper fixture to create a mock client with custom responses."""
    def _create_client(responses):
        def mock_handle_request(request: httpx.Request) -> httpx.Response:
            return responses.pop(0)
        return Client(
            base_url=None,
            dry_run=True,
            token="",
            mounts={"'http://": httpx.MockTransport(mock_handle_request)},
        )
    return _create_client

and use client = mock_client(responses)