fix(weixin): avoid cross-loop live session reuse

[LeonSGP43]

Summary

• only reuse the live Weixin adapter when its aiohttp send session belongs to the current event loop
• fall back to a temporary session for sync bridges like send_message and cron delivery
• add a regression test that covers the foreign-loop live adapter path

Closes #13099

Testing

• pytest -o addopts='' tests/gateway/test_weixin.py

[alt-glitch]

Related to #13350 and #12810 (same cross-loop reuse fix for Weixin). May supersede both — verify which should be merged.

[alt-glitch]

Related to #13350 and #12810 (same cross-loop reuse fix for Weixin). May supersede both — verify which should be merged.

[teknium1]

Thanks for the focused diagnosis and regression direction. This is already implemented on current main.

Automated hermes-sweeper review verified:

• gateway/platforms/weixin.py:2307-2311 permits live-adapter reuse only when send_session._loop is asyncio.get_running_loop().
• A loop mismatch falls through to the fresh aiohttp.ClientSession path at gateway/platforms/weixin.py:2336, preserving delivery from sync bridges and cron.
• The exact fix landed in a22465e07ab4b71019f711e7a6463f6590c50742 (fix(weixin): send_weixin_direct cross-loop session check) and shipped in v2026.5.7.
• This matches the duplicate-cluster discussion linked by the maintainer on fix: avoid cross-loop reuse in weixin direct send #13350 and fix(weixin): skip live adapter reuse in send_weixin_direct when on a different event loop #12810.

Closing as implemented on main.