## What changed
Add optional `request_permissions` and `auto_review_suffix` fields to catalog approval messages. Use them to customize the permission tool heading and introduce automatic review guidance while preserving the bundled instruction bodies and existing policy gates. Accept `request_permissions_tool` as a deserialization alias.
Limit headings to 500 UTF-8 bytes on a single line and fall back to bundled text for missing or invalid values. Complete catalog approval messages retain precedence.
## Testing
Add coverage for heading validation, serialization aliases, policy gates, fallback behavior, and complete-message precedence. Integration tests verify that model switches append the selected model's headings without rewriting history or repeating unchanged instructions.
GitOrigin-RevId: 3311591a464cc086783fe25271a352dd5a229790