v0.6.0

Breaking changes

• Buf is now lifetime-bound as Buf<'a> and borrows &'a ZeroPool.
• ZeroPool no longer implements Clone; share it with &pool in scoped threads or Arc<ZeroPool> for owned thread sharing.
• Removed the tokio-uring feature and IoBuf/IoBufMut impls. Use buf.into_vec() when an owned buffer is required.
• Runtime stats are opt-in via .track_stats(true); the default hot path avoids stats atomics.

Highlights

• Removed hot-path Arc clone by making Buf<'a> borrow the pool.
• Added opt-in stats tracking after profiling showed relaxed atomics were measurable in tight loops.
• Rebuilt the Criterion benchmark suite with shared helpers and comparison crates behind --features bench.
• Added BENCHMARKS.md with methodology, environment, results, and reproduction commands.
• Removed obsolete examples/ files.

Validation

• CI passed on PR #8.
• cargo fmt --all -- --check
• cargo clippy --all-targets --all-features -- -D warnings -A unsafe_code
• cargo test --all-features