unstructured

8745e7c9 - Fix Docker ARM64 image failure, use 8-core github runners (#4232)

Fix Docker ARM64 image failure, use 8-core github runners (#4232) <!-- CURSOR_SUMMARY --> > [!NOTE] > **Medium Risk** > Changes are confined to CI/CD and build tooling, but runner/driver updates can cause unexpected workflow failures or behavior differences in Docker builds/tests across architectures. > > **Overview** > **CI/CD infra updates for faster, more reliable pipelines.** CI jobs that run heavier integration/fixture/Dockerfile tests now use `opensource-linux-8core` instead of `ubuntu-latest-m`. > > **Docker publish now builds ARM64 natively.** The `docker-publish` workflow runs `linux/arm64` builds on `opensource-linux-arm64-4core`, removes QEMU setup, and simplifies buildx to use the `docker` driver. > > **Release housekeeping.** Adds `.python-version` (and stops ignoring it), enables `pytest -n auto` in the `docker-test` target, updates `CHANGELOG.md`, and bumps `unstructured/__version__.py` to `0.19.2`. > > ^{Written by [Cursor Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit 50c09e1fa078eddbc99b603ffc0e5f038cb4b003. This will update automatically on new commits. Configure [here](https://cursor.com/dashboard?tab=bugbot).} <!-- /CURSOR_SUMMARY -->