Context managers leave the companion HTTP client open

[saxon134]

GlobalRouter.__init__ always creates both self._client and self._async_client, but close() only closes the sync client and aclose() only closes the async client. A sync with GlobalRouter(...) therefore leaves the async client's connection pool open, while async with GlobalRouter(...) leaves the sync client open. This is directly reproducible with c = GlobalRouter(api_key='x'); c.close(); assert c._async_client.is_closed, which fails. The lifecycle methods should close both clients, or the SDK should lazily create only the client flavor being used.

File: src/globalrouter/_client.py

Line: 77

Severity: medium

Summary: unclosed companion client in globalrouter lifecycle

[saxon134]

Coding Loop Plan

Refined Issue

Context-manager exits should release both internally-created HTTP clients. The synchronous context manager currently closes only the sync httpx.Client, and the asynchronous context manager currently closes only the async httpx.AsyncClient, leaving the companion client open.

Implementation Plan

Implementation Plan

Add focused regression coverage for both sync and async context-manager exits, then update the GlobalRouter lifecycle methods so leaving either context closes both underlying HTTP clients. Keep the change limited to lifecycle behavior and avoid unrelated API or resource refactors.

Development Tasks

1. Add regression tests for companion client closure
   Add tests that prove both context-manager variants close both underlying HTTP clients. For the sync case, create a GlobalRouter, enter and exit with client:, then assert client._client.is_closed and client._async_client.is_closed. For the async case, create a GlobalRouter, enter and exit async with client:, then assert both is_closed flags. Use mock transports and an explicit API key to avoid network access. These tests should fail before the implementation fix.
   Files: tests/test_client.py
   Tests: pytest tests/test_client.py -k 'context or close' -q, pytest tests/test_client.py -q

2. Close both HTTP clients from context-manager exits
   Update GlobalRouter lifecycle behavior so exiting the synchronous context manager closes the sync client and also closes the async client, and exiting the asynchronous context manager closes the async client and also closes the sync client. Keep close() and aclose() idempotent by checking the clients' is_closed flags before closing. For sync closure of the async client, use a bounded approach that works in normal synchronous context-manager use, such as running self._async_client.aclose() only when it is not already closed. For async closure, call self._client.close() directly if it is not already closed. Do not change request behavior, retry behavior, or resource APIs.
   Files: src/globalrouter/_client.py, tests/test_client.py
   Tests: pytest tests/test_client.py -k 'context or close' -q, pytest tests/test_client.py -q, ruff check src tests, mypy src