Merge pull request #5 from triblespace/codex/add--features--section-to-readme

Add README features section

Author: somethingelseentirely

README.md

@@ -13,6 +13,17 @@ and is implemented for a variety of sources already,
 including other byte handling crates `Bytes`, mmap-ed files,
 `String`s and `Zerocopy` types.
 
+## Features
+
+By default the crate enables the `mmap` and `zerocopy` features.
+Other optional features provide additional integrations:
+
+- `bytes` – support for the [`bytes`](https://crates.io/crates/bytes) crate so `bytes::Bytes` can act as a `ByteSource`.
+- `ownedbytes` – adds compatibility with [`ownedbytes`](https://crates.io/crates/ownedbytes) and implements its `StableDeref` trait.
+- `mmap` – enables memory-mapped file handling via the `memmap2` crate.
+- `zerocopy` – exposes the [`view`](src/view.rs) module for typed zero-copy access and allows using `zerocopy` types as sources.
+- `pyo3` – builds the [`pybytes`](src/pybytes.rs) module to provide Python bindings for `Bytes`.
+
 ## Comparison
 
 | Crate | Active | Extensible | mmap support | Zerocopy Integration | Pyo3 Integration | kani verified |