Build G: pin-bump validation pass (pe-us 1.752.2 → 1.764.0) before the next release build

Build G opens with a pin-bump validation pass, per discussion with Max (2026-07-06).

Opener (committed): pin-bump validation pass before any build

policyengine-us moved 1.752.2 → 1.764.0 (28 releases) during the Build F campaign. Before Build G commits to a pin:

1. Resolve the current policyengine-us in a fresh env and run, against the Build F base artifact:
   • the eCPS parity gate (ratchet mode) — expect legitimate state-income-tax deltas from the 1.756.9 uprating-placement fix (33 frozen parameter files across ME/NE/ND/NY/OH/RI now uprate); triage each delta into the reason'd register deliberately,
   • the engine-asserted take-up contract (#315) — confirm no model-side seeding appeared for data-seeded flags,
   • critical-fit spot checks (income tax, SS) — quantify model-drift movement before calibration sees it.
2. Record the resolved version; checkpoints invalidate automatically (version is in the cache key by design, #317).

Candidate program (proposed, not yet committed)

• Accuracy-exemption cluster from the parity register: #253 (tuition), #252 (auto-loan interest), #254 (AMT preference items), #298 (QBI benchmarks).
• #296 ASEC 2024+2025 ingest (spine two vintages behind).
• SNAP work-requirement input carriage (#248/#249/#250, with #293/#294): newly elevated — pe-us 1.758–1.764 shipped the ABAWD/work-requirement engine hooks (exemption inputs, workfare hours, borough-level waivers by county FIPS, HR1 state coverage), which consume person-level inputs populace does not yet carry; HR1 SNAP analyses run on proxies until it does.
• #321 CHIP concept mapping (M-CHIP vs separate CHIP at the ledger level).

Sequencing and scope decisions for the program remain open pending Build F's gate tables (#299).

Start by resolving the current policyengine-us version in a fresh environment and running the eCPS parity gate in ratchet mode against the Build F base artifact. Then run the engine-asserted take-up contract (#315) and critical-fit income-tax and Social Security spot checks. Record the resolved version, triage each parity delta into the reasoned register, and quantify model-drift movement before calibration.