[codex] Refresh Credible Layer docs

[odyslam]

Summary

This PR refreshes the Credible Layer docs using recent product source material, then applies a Diataxis pass so the added material fits the existing docs model.

Key changes:

• Clarifies the Credible Layer product lifecycle across authoring, testing, staging, promotion, enforcement, incidents, ownership verification, and project management.
• Adds and updates platform screenshots for project creation, project dashboard, audit log, project settings, and public explorer surfaces.
• Adds network-facing integration content for the Assertion Enforcer, network integration overview, OP Stack architecture, L1-originated transaction policy, and production assertion admission.
• Reframes public docs away from caveat-forward language while keeping the operational facts needed by protocol and network operators.
• Adds pnpm supply-chain hardening with minimumReleaseAge: 14400 and pins pnpm to a version that supports it.

Validation

• pnpm validate
• pnpm broken-links

Both commands pass locally. The local shell reports the existing engine warning because the repo expects Node 24.x and this machine is currently running Node v25.9.0.