## Why
Clients that complete an external agent config import outside the app server need a way to include the result in import history.
## What changed
- Add `externalAgentConfig/import/recordHistory` to persist completed item results and return a generated import ID.
- Store the optional provider ID for regular imports and expose it when reading import history.
- Update the generated JSON and TypeScript protocol schemas for the new request, response, and history field.
## Testing
- Cover recording and reading an externally completed import through the app-server protocol.
- Cover provider ID persistence and updates in the state runtime.
GitOrigin-RevId: 935401e899ec9eeb38f54c182e45a16642411deb