Deprecation of a1-standard-4 in Semaphore

Semaphore will retire the a1-standard-4 machine type on October 15, 2025, requiring all projects that utilize this type in their pipelines to transition to the a2-standard-4 machine type. Impacted users can identify whether they need to make this change by checking their pipeline settings in the Workflow Editor or by searching for the a1-standard-4 string in their repository's YAML files. To prepare, users should update their configurations by either changing the machine type in the Workflow Editor or by replacing a1-standard-4 with a2-standard-4 in their pipeline YAML files. When making this switch, users are advised to update their macOS/Xcode images to a supported version, with macos-xcode16 recommended as a baseline. All users have access to the a2-standard-4 without any additional setup, and assistance is available through Semaphore's support email or Discord community for those needing help with the migration.