Adam PDF417 guide-crop design observation (2026-09-08; source: current origin/staging code…

Adam PDF417 guide-crop design observation (2026-09-08; source: current origin/staging code review): a concurrent guide decoder must be represented as one parser-validated attempt through Adam’s existing admission/scheduler/worker-pool accounting; an out-of-band guide job can exceed the C20 budget and cannot satisfy the existing winner/attempt response invariants. Preserve raw-JPEG legacy behavior behind a Shield-side exact-true feature gate, and validate multipart aggregate plus per-part bounds before forwarding.