Summary

Add a user guide documenting the best practice for using the ROCK Job system to collect Agent trajectories for model distillation training.

Motivation

Trajectory distillation (using a strong Teacher model's behavioral data to train a weaker Student model) is a common use case for the Job system, but there is currently no documentation covering this workflow end-to-end.

Scope

• User guide document (Chinese + English) under docs/versioned_docs/version-1.7.x/User Guides/
• Example code and config template under examples/trajectory_distillation/
• Covers: quick start (end-to-end runnable example), configuration details, trajectory data reference (result.json + trajectory.json), advanced usage (async mode, rejection sampling, DPO pairs)
• Validated against a real ROCK deployment with swe-agent on SWE-bench