Production code fixes:
- scheme.rs: replace unwrap() after checked_mul with match binding,
eliminating a latent panic if code is reordered
- main.rs: log request context_id (PID) on request handling failure
instead of silently discarding the error
- drivers/amd/display.rs: split silent EDID read fallback into
separate match arms with log::warn diagnostics for short reads
and read failures, including byte count and connector index
Test coverage:
- gem.rs: add 4 basic tests for GemManager (create+verify,
close+verify removal, double-close error, invalid handle error)
vasilito
e62acb2ebb