Optimize agent state path and worker timing

[w1kke]

Summary

• remove the redundant /api/state route and trim irrelevant stats fields so the worker sees only the data it needs
• limit the OpenClaw worker fallback to 50 and surface the constraint in the docs
• fix transcript-repair timing so synthetic tool results are appended after turns instead of mid-turn and keep /api/state off the hot-path store reads
  Testing
• Not run (not requested)