Implement Riverbraid-Golds registry scaffold without claim inflation

[Riverbraid]

Purpose

Use the supplied Riverbraid-Golds implementation packet as a source seed for a bounded registry scaffold.

This issue is an implementation tracker, not a functional-status claim.

Scope

• Gold metadata registry.
• Lifecycle statuses: experimental, functional, production-ready, deprecated.
• Evidence gates for status promotion.
• Expansion-gate handling with default active-entry limit of 30 unless approved exception exists.
• Succession procedures for registry continuity.
• Claim and evidence ledgers tied to actual verification records.
• Reviewer-facing status surfaces.

Order

1. Inventory current repository behavior.
2. Add documentation scaffold and normalized ledgers.
3. Normalize API names before source implementation.
4. Add minimal source modules.
5. Add tests matching the chosen API.
6. Record execution output before any pass claim.
7. Leave workflow/release changes for a separate approval gate.

Required corrections

• Preserve the current non-claim boundary.
• Do not mark the repository Functional until evidence supports it.
• Do not claim exact Gold counts without active registry evidence.
• Do not add pass/fail ledger rows without real records.
• Do not represent placeholders as completed trust mechanisms.
• Do not overwrite current verifier scripts without a migration path.

Linked plan

See docs/RIVERBRAID_GOLDS_IMPLEMENTATION_PLAN.md.