Audit v3 fixes: all 3 tiers (19 findings)

Tier 1 (compilation + correctness):
- Fix nightly-only is_multiple_of → % 2 != 0 (stable Rust compat)
- Fix parse_sample_rate: check 192 before 96 (was returning wrong rate)
- macOS drive discovery: split unix.rs → linux.rs + macos.rs
- Linux: EACCES returns DevicePermission not DeviceNotFound
- CLI pipe.rs: Ctrl+C signal handler added

Tier 2 (correctness + security):
- MkvStream: reset demuxer after scanning→streaming transition
- Windows SPTI: zero data buffer before ioctl
- AACS cert verification: documented why silently skipped
- KEYDB: HOME + USERPROFILE fallback for Windows
- Library modules: pub(crate) for internal modules
- AACS: explicit re-exports, AES primitives pub(crate)

Tier 3 (performance + polish):
- IsoStream: batch 64-sector reads (was 1 sector at a time)
- DiscStream: buffer swap instead of copy in decrypt_and_buffer
- Vec capacity hints in TS/PS demuxer hot paths
- NetworkStream: TLS warning documented
- Batch rip: per-title progress display
- cargo fmt: 0 violations

319 tests, 0 fmt violations.

src/drive/windows.rs

@@ -43,6 +43,10 @@ pub fn resolve_device(path: &str) -> Result<(String, Option<String>)> {
 /// Normalize a device path to Windows \\.\X: format.
 ///
 /// Accepts: "D:", "D:\\", "\\.\D:", "\\.\CdRom0"
+///
+/// NOTE: A near-identical `normalize_device_path` exists in `scsi::windows`.
+/// Both are kept because they live in separate `cfg(windows)` modules that
+/// cannot easily share a helper without introducing cross-module coupling.
 fn normalize_path(path: &str) -> String {
     if path.starts_with("\\\\.\\") {
         return path.to_string();