rc2: macOS cross-compile fix + security/recovery hardening

- build.rs: pass target -arch to cc so macos_shim cross-compiles (x86_64-apple-darwin)
- AACS/CSS: unit-aligned decrypting sweep; per-VTS CSS title keys (hard-fail on wrong VTS);
  reject truncated Unit_Key_RO; AACS 2.0 sig-verify skip; CSS bus-auth random nonce
- recovery: gap-filling mapfile load; sweep/copy resume reconciliation; stale-mapfile abort;
  patch wedge/damage-window range reset
- mux: TS continuity + PSI CC desync guards; HEVC numTemporalLayers clamp; MPEG-2 pending
  byte-cap; PS parse_pts marker-bit validation; HdrFormat strict parse; Unknown-variant metadata
- net/keydb: network:// SSRF parity (IPv4-mapped, CGNAT, 0.0.0.0/8, Class-E); bounded keydb
  header read + size cap + error context
- io: durable mapfile fsync; NFS writeback degrade; sync_file_range error capture;
  Windows SCSI u32 transfer guard

src/mux/codec/mod.rs

@@ -105,7 +105,7 @@ impl PassthroughParser {
 
 impl CodecParser for PassthroughParser {
     fn parse(&mut self, pes: &PesPacket) -> Vec<Frame> {
-        let pts_ns = pes.pts.map(pts_to_ns).unwrap_or(0);
+        let pts_ns = pes.pts.or(pes.dts).map(pts_to_ns).unwrap_or(0);
         vec![Frame {
             pts_ns,
             keyframe: self.keyframe,