* Fix#666: TSAN builds don't actually use threads
TSAN builds did not explicitly enable MULTITHREAD_SUPPORT_ENABLED, so they
relied on the CMake default. This adds -DMULTITHREAD_SUPPORT_ENABLED=ON to
both TSAN jobs and expands the CI matrix to cover threading on/off with
Debug/Release for Linux, macOS, and Windows MSVC. Also excludes async-dependent
.chai tests from non-threaded builds and adds a Threading_Config_Test to verify
the threading configuration is correct in both modes.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
* Address review: use Ninja generator for all unix CI targets
Requested by @lefticus in PR #670 review.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
---------
Co-authored-by: leftibot <leftibot@users.noreply.github.com>
Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
