## What changed
- Add a reusable transcript contributor for synchronous and asynchronous Guardian context, with borrowed conversation history and request-specific configuration.
- Preserve conversation order and role or tool attribution while applying separate per-entry limits for messages, ordinary tools, and Node REPL-backed outputs.
- Make tool calls, tool outputs, and reasoning independently configurable, and expose transcript collection without requiring section composition.
- Register the transcript contributor in a process-wide default registry that retains no request state.
## Testing
- Add unit coverage for role and tool attribution, optional evidence sources, orphaned and named tool outputs, registry reuse, and request-specific entry limits.
GitOrigin-RevId: 2b60f8db4618de8a7175f8ee0183375a526a87db
0918cd2c08