fix(deps): declare typing_extensions and use stdlib NotRequired on 3.11+

[joerg84]

Problem

Clean installs on Python 3.13+/3.14 fail at import pinecone: _internal/indexes_helpers.py imports NotRequired from typing_extensions, which is not declared in [project] dependencies. It worked by accident — httpx → anyio only pulls typing_extensions on python_version < "3.13", and dev/CI environments always carry it via mypy. The unit-test matrix capping at 3.13 completed the blind spot.

Fix

• Version-gate the import: stdlib typing.NotRequired on 3.11+, backport on 3.10.
• Declare the real remaining dependency: typing_extensions>=4.0; python_version < '3.11'.
• Add 3.14 to the unit-test matrix and the trove classifiers so a clean-install regression can't hide behind dev dependencies again.

Testing

• Verified on a bare Python 3.14 venv with only httpx[http2], msgspec, orjson installed: pinecone._internal.indexes_helpers imports cleanly (fails with ModuleNotFoundError on main).
• uv run pytest tests/unit: 4376 passed. (test_socket_options.py linux/darwin keepalive tests fail identically on clean main on macOS — pre-existing, untouched.)
• ruff check, ruff format --check, mypy --strict clean on the touched file.

Fixes #690

Found by a cold-agent audit (2/2 bare-environment trials hit this on first import).

🤖 Generated with Claude Code

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Note

Low Risk
Dependency and import-path fixes with narrow typing backport scope; test-only asyncio API changes; no runtime behavior change beyond fixing missing dependency on newer Python.

Overview
Fixes clean-install import failures on Python 3.13+ where indexes_helpers pulled NotRequired from typing_extensions without it being a declared runtime dependency.

NotRequired sourcing is version-gated in indexes_helpers.py: stdlib typing on 3.11+, typing_extensions only on 3.10. pyproject.toml adds typing_extensions>=4.0; python_version < '3.11', documents Python 3.14 in trove classifiers, and CI unit tests now include 3.14 in the matrix.

Unit tests that drove async coroutines via asyncio.get_event_loop().run_until_complete now use asyncio.run (batch and retry transport). uv.lock is refreshed (package version and dependency marker cleanup).

^{Reviewed by Cursor Bugbot for commit 18b4ae9. Bugbot is set up for automated code reviews on this repo. Configure here.}

[joerg84]

The new py3.14 matrix job immediately caught a real 3.14 incompatibility: six test drivers used asyncio.get_event_loop().run_until_complete(...), and 3.14 removed implicit loop creation from get_event_loop() (RuntimeError instead of a DeprecationWarning'd fresh loop). Pushed a commit replacing those six sites with asyncio.run(...) — product code had zero get_event_loop uses. Full unit suite verified locally on both 3.14 (4,599 passed) and 3.12.