BFE EngineeringandClaude Opus 4.8
1752dea7b6
Bring relays.c into warden-sdk/drivers/ behind a relay_io seam (ADR-0005): the sysfs plumbing is an injectable backend, the gpio root is $WARDEN_GPIO_ROOT- overridable. Host harness (drivers/relays/test/) reaches 100% MC/DC (40/40 conditions, 100% lines) by combining fake-io unit tests (logic branches incl. export->node-appears) with real-sysfs integration tests over a scratch tree (backend fopen/stat branches). CI `mcdc` job enforces 100% across drivers/*/test. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_017wB8KB3MMQztRDXCMCkPrf