Establish canonical protocol configuration and cross-layer consistency

[0xjei]

This parent tracks the migration from scattered protocol constants to explicit, verifiable sources of truth.

The work must distinguish:

• Protocol parameters that affect proofs, hashes, committee selection, deployment, or wire compatibility.
• Circuit-bound configuration that is generated from those parameters.
• Local operational defaults and test-only fixtures that should not become protocol configuration.

The migration must preserve parameter identities, circuit witness shapes, committee thresholds, and deployed compatibility. Child issues cover the constants migration, default BFV safety, terminology, and documentation drift.