Add typed scientific persistence artifacts

[mveril]

Summary

• Add RustiQData as the typed scientific persistence facade with lazy AO ERI loading.
• Keep manifests, physical storage selection, filesystem details, and NPY conversion infrastructure internal.
• Add focused public ArtifactError and NpyError types while keeping storage/manifest/orchestration errors internal.
• Add internal folder storage with streaming size/SHA-256 accounting and a concrete dispatch point that can host the future ZIP/ZIP64 implementation without exposing a generic storage backend.
• Add portable path validation and real NumPy C/Fortran matrix interoperability fixtures.
• Route the directory-backed ERI cache through the internal persistence machinery and document the V1 logical format.

Verification

• cargo test --workspace --all-targets --all-features --quiet
• cargo test --workspace --all-targets --no-default-features --quiet
• cargo clippy --workspace --all-targets --all-features -- -D warnings
• cargo fmt --all -- --check

No sample inputs or expected numerical results changed.