Python: fix(redis): close an owned RedisContextProvider index on exit

[Yufeng He (he-yufeng)]

Fixes #9509

Root cause

RedisContextProvider builds its own AsyncSearchIndex from redis_url when no index is injected, but its __aexit__ was empty and there was no aclose — so the connection pool behind that index was never released. Providers created and discarded per session leak open sockets. RedisHistoryProvider in the same package already closes a client it owns (_owns_client + aclose); the context provider was the outlier.

Fix

Mirror the sibling's ownership rule:

• _owns_index = redis_index is None recorded at construction;
• new aclose() disconnects the index (redisvl AsyncSearchIndex.disconnect()) only when owned — an injected index stays under the caller's control;
• __aexit__ now calls aclose().

Test plan

New TestRedisContextProviderClose (next to the history provider's close tests), reusing the existing patch_index_from_dict/mock_index fixtures:

• owned index → disconnect() awaited on aclose();
• injected index → not disconnected;
• async with exit → owned index disconnected.

On the unpatched code both owned-index tests fail (nothing to assert against fires); the borrowed-index test passes both ways, as it should. Verified locally with the redis + core packages from this branch on the repo venv:

python -m pytest packages/redis/tests/     # 328 passed, 48 skipped
ruff check / ruff format --check           # clean

[Copilot]

🟢 Approval recommended

The focused fix preserves caller ownership and covers the intended cleanup paths with regression tests.

No open issues 🎉

What changed in this PR

Fixes #9509 by releasing Redis connections owned by RedisContextProvider, while leaving injected indexes under caller control.

Changes:

• Tracks index ownership and adds aclose().
• Calls cleanup when the async context manager exits.
• Adds regression tests for owned and borrowed indexes.

File	Description
python/​packages/​redis/​tests/​test_providers.py	Tests explicit cleanup, borrowed-index preservation, and context-manager exit.
python/​packages/​redis/​agent_framework_redis/​_context_provider.py	Adds ownership-aware cleanup for the Redis index.

_{Review effort: Balanced}