fix: publish manylinux wheels accepted by PyPI

[jamesdborin]

Summary

• disable reqwest default features so rustls is used without OpenSSL/native-tls
• build Linux release wheels with manylinux 2_28 tags for PyPI compatibility
• keep existing multi-platform wheel publish flow

Validation

• cargo check --manifest-path rust/Cargo.toml --all-targets
• cargo test --manifest-path rust/Cargo.toml
• maturin build --release --manifest-path rust/Cargo.toml --features python --out dist
• python API smoke test from CI
• CLI smoke test from CI