docs: add Quantum read-path adapter checklist

[williamclay8]

Summary

• adds a docs-only Quantum read-path adapter conformance checklist for explorers, indexers, analytics, and APIs
• links the checklist from the developer docs index and the Quantum adapter touchpoint manifest
• focuses on preserving native transaction evidence such as 0x7A, explicit sender, 2D nonce fields, keyId, signature-role metadata, receipts/logs, token-transfer views, unknown fields, and millisecond timestamp data

Boundaries

• docs only; no code, runtime, wallet, signing, faucet, bridge, broadcast, or transaction-flow changes
• no production-readiness, audit, maintainer-acceptance, live-network, mainnet, airdrop, reward, or financial claims
• public reports are framed around redacted field presence, role labels, byte lengths, source labels, and pass/fail/warning/not-covered rows

Verification

• git diff --cached --check
• checked the new doc for public-claim risk terms before commit