Refresh US bundle to policyengine-us 1.715.2

[anth-volk]

Fixes #384

Summary

• Refreshes the bundled US release manifest and TRACE TRO to policyengine-us==1.715.2 while keeping policyengine-us-data==1.115.5.
• Pins the US data release manifest revision that adds policyengine-us==1.715.2 as an explicit compatible model package: https://huggingface.co/policyengine/policyengine-us-data/discussions/1
• Updates bundle refresh certification logic so explicit compatible-model assertions are recorded as legacy_compatible_model_package rather than matching_data_build_fingerprint.
• Allows offline bundled-certification fallback for explicit compatible-model assertions where runtime and build data fingerprints are expected to differ.

Validation

• POLICYENGINE_SKIP_COUNTRY_IMPORTS=1 uv run pytest --noconftest tests/test_bundle_refresh.py
• HUGGING_FACE_TOKEN=$(cat ~/.cache/huggingface/token) POLICYENGINE_SKIP_COUNTRY_IMPORTS=1 uv run --extra uk --extra us pytest --noconftest tests/test_release_manifests.py tests/test_trace_tro.py
• ruff check src/policyengine/provenance/bundle.py src/policyengine/provenance/manifest.py tests/test_bundle_refresh.py tests/test_release_manifests.py

Notes

This is draft until the linked Hugging Face compatibility-manifest PR is accepted or we decide that pinning the HF PR commit directly is acceptable.