Add 40 arXiv paper study cards

[estelledc]

Summary

• Add 40 new study-v2 paper study cards across 10 batches (4 papers each).
• Add matching study-review-receipt-v1 static review receipts for all 40 notes.
• Refresh papers atlas / note index and public scale copy from 1023 papers to 1063 papers (2024 total notes).
• Update SESSION-HANDOFF.md with the bounded epoch contract and local verification evidence.

Verification

• arXiv metadata check: 40/40 entries resolved via official arXiv API.
• node scripts/quality-gate.mjs --changed-from main --json → checked=40, pass=true.
• npm run atlas → 2024 notes, 69 chunks.
• npm run audit:counts
• npm run audit:content-contract
• npm run audit:links
• npm run audit:wikilinks
• git ls-files -co --exclude-standard -z | node scripts/audit-public-redlines.mjs --stdin0
• npm run build:strict -- --log /tmp/study-forty-build-clean.log
• STUDY_CHANGED_FROM=384787e09827c336baf5ac2b33e67e8c91b9df49 STUDY_BUILD_LOG=/tmp/study-forty-verify-build.log npm run verify:ci

Trust Boundary

All 40 new notes are STATIC_ANALYSIS / UNVERIFIED; no paper benchmark or author repository was executed.