Reconcile Tensor agent authority routing

[iteathen]

Purpose

Complete the CUDA-JS-Tensor side of the account-global agent-authority migration and remove a stale live-compatibility claim from the registry.

Changes

• add agent_files/README.md as the current local routing/classification index
• route reusable doctrine through account-global AGENTS → repository AGENT_LOCAL
• classify old AI/design/principles files as retained legacy where they overlap global doctrine
• make System Registry explicitly component/source routing rather than an agent manual
• stop duplicating a live CUDA-JS dependency in the registry; current package identity remains single-owned by package/lock/protected-state/next-step surfaces

No Tensor mathematics, public ABI, package dependency, runtime implementation, compatibility decision, or support evidence changes.