## What changed
- Add a hidden global `--psp` runtime flag and propagate it through TUI, exec,
app-server, remote-control, and in-process startup paths.
- Attach the `oai-chat-psp=true` cookie to first-party ChatGPT requests when
enabled, using a cached cookie-aware client with sensitive request logging
disabled.
- Keep the routing selection out of persistent configuration layers while
preserving it across config refreshes and agent role changes.
## Testing
- Cover global flag parsing, app-server propagation, config-layer isolation,
and preservation across config rebuilds and role changes.
GitOrigin-RevId: 05cdc61ffd7162d8e48fc1e166f4732113e5a816