Add decrypt module, merge to one drive.read(), Disc::decrypt_keys()

- New decrypt.rs: DecryptKeys enum (AACS/CSS/None) + decrypt_sectors()
- Single drive.read() replaces read_disc/read_content (same SCSI READ(10))
- ContentReader and DiscStream use decrypt_sectors() (no duplicated crypto)
- Disc::decrypt_keys() exposes resolved keys for disc-to-ISO

src/lib.rs

@@ -68,6 +68,7 @@
 pub mod aacs;
 pub(crate) mod clpi;
 pub mod css;
+pub mod decrypt;
 pub mod disc;
 pub mod drive;
 pub mod error;
@@ -107,6 +108,7 @@ pub use mux::NetworkStream;
 pub use mux::NullStream;
 pub use mux::StdioStream;
 pub use mux::{open_input, open_output, parse_url, InputOptions, StreamUrl};
+pub use decrypt::{DecryptKeys, decrypt_sectors};
 pub use scsi::ScsiTransport;
 pub use sector::SectorReader;
 pub use speed::DriveSpeed;