API: Drive object, typed StreamUrl, tray lock/unlock, Send traits

- Rename DriveSession → Drive across entire codebase
- find_drives() returns Vec<Drive>, find_drive() returns Option<Drive>
- resolve_device() now pub(crate) — internal only
- StreamUrl is now a typed enum (Disc, Mkv, M2ts, Iso, Network, Stdio, Null)
  with scheme() and path_str() accessors, replacing struct of Strings
- Add lock_tray() / unlock_tray() for safe disc access during rips
- Improve reset() with eject cycle that clears LibreDrive stuck state
- Add Send bounds to ScsiTransport and PlatformDriver traits
- DiscOptions uses PathBuf instead of String for device/keydb paths
- Update doc example to use new Drive API

src/aacs/keys.rs

@@ -449,7 +449,7 @@ const MKB_PACK_SIZE: usize = 32772;
 /// Read MKB from drive via SCSI (REPORT DISC STRUCTURE format 0x83).
 /// Returns the concatenated MKB data from all packs.
 pub fn read_mkb_from_drive(
-    session: &mut crate::drive::DriveSession,
+    session: &mut crate::drive::Drive,
 ) -> crate::error::Result<Vec<u8>> {
     use crate::scsi::{DataDirection, SCSI_READ_DISC_STRUCTURE};