Standardize policy names across code/YAML/UI/docs

[susheem-k]

Summary

Policy identifiers / display names are inconsistent across code, YAML, and docs (harder to learn, wire, and compare).

Area: src/tokenops/control/policies/*, config YAML, Admin UI, docs

Desired behavior

• One canonical name per policy (code module, YAML key, UI label mapping, docs slug).
• Document the naming convention (e.g. snake_case detector id = config key).
• Rename/alias plan for any legacy names so demos and seeded default.yaml stay coherent.

Acceptance sketch

• Single glossary of policy ids; no duplicate aliases without an explicit deprecation path.

Reference: docs/notes/2026-07-23-design-fix-notes.md §2