Populate AOTC eligibility inputs

[MaxGhenis]

Summary

• convert the PUF-imputed tax-unit AOTC signal into lower-level Enhanced CPS AOTC eligibility inputs
• fill qualified tuition expenses when a positive imputed AOTC unit lacks a tuition recipient
• avoid writing all-false AOTC inputs when there is no positive imputed AOTC signal

Dependency

• Depends on Add education credit eligibility inputs policyengine-us#8170 for the new AOTC eligibility input variables.

Tests

• uv run ruff format policyengine_us_data/datasets/cps/extended_cps.py tests/unit/test_extended_cps.py && uv run ruff check policyengine_us_data/datasets/cps/extended_cps.py tests/unit/test_extended_cps.py
• uv run pytest tests/unit/test_extended_cps.py -q

Fixes #841

[MaxGhenis]

Closing because this repository's CI requires PR branches to live in PolicyEngine/policyengine-us-data rather than a fork. Reopening from an upstream branch.