docs: add autoresearch operating contract

[Cossackx]

Summary

• Add docs/swarm/AUTORESEARCH.md, a source-owned operating contract for bounded autoresearch loops.
• Link the contract from Swarm docs and researcher role/profile guidance.
• Capture entry criteria, iteration discipline, logging, role ownership, reward-hacking red flags, and pilot templates for skills, profiles, GBrain retrieval, repo cleanup, and browser QA.

Verification

• DOC_SMOKE_OK Python content smoke for the new doc and links.
• git diff --check.

Notes

• This is the focused, conflict-free doc slice from the broader semantic-swarm branch.
• Prior broad PR feat: align semantic Hermes swarm agents #424 was closed unmerged; PR feat: align semantic swarm agents and autoresearch contract #434 is superseded by this focused branch if we only want to land the autoresearch contract now.