Add opt-in bounded output-schema advertisements while preserving the full default, canonical server validation and complete structured content. Verify real stdio discovery under a 1 MiB receive cap, all 5,367 libcrypto export coordinates, complete Evidence parity, whole-task serialization estimates and resource bounds.
Fixes#2512. Integrates #7054 by Akshad Jogi with original authorship retained.
Co-authored-by: Akshad Jogi <[email protected]>
