Sprint 9.3 — Cleaner and verification properties

[maruson08]

Scope

For structurally valid generated/canonical JPEG, WebP, and PNG inputs, cover:

• deterministic and idempotent cleaning
• source immutability and re-inspectable output
• fail-closed verification for incomplete/truncated reports
• default ICC and unknown-structure preservation
• format-specific scan/image, RIFF/VP8X, and retained PNG chunk/CRC invariants

Definition of Done

• generated properties model legitimate format-specific mutations accurately
• successful output is structurally complete and bounded by current removal-only sizing
• incomplete structures never produce partial clean output or passing verification