Fixed Rust version compatibility by pinning oxigraph
dependency to 0.5.2, ensuring support for Rust 1.70.0+ (resolving issues
with newer oxigraph requiring bleeding-edge Rust).
Added libsnappy-dev to SystemRequirements for RocksDB
compression support.
Fixed linker warnings on macOS ARM64 (M1/M2) builds by setting a
default MACOSX_DEPLOYMENT_TARGET.