docs: add PDP calibnet runbook and caveats for scheduling

[anjor]

Summary

• add the PDP calibnet end-to-end runbook under docs topics
• document PDP operational caveats in deal-pusher and schedule docs
• add explicit guidance for CommPv2/CommP CID acceptance, piece-size cap, sybil-fee requirement, and ETH RPC usage

Context

• part of PDP calibnet E2E: CommPv2 validation gaps, addPieces gas-limit failure, and listener/createDataSet edge cases #631

[parkan]

superseded by #640 which landed the runbook and code changes. cherry-picking the SUMMARY.md sidebar link and deal-schedule caveats separately.