Account for decrypt-time loss so partial AACS/CSS failures can't pass as a perfect rip

When a scrambled AACS unit fails to decrypt under every available key
(a missing/wrong CPS sub-key, or a marginal unit that fails the TS-sync
verify), decrypt_sectors restored the original encrypted bytes and
returned Ok with no signal. Those still-encrypted bytes flowed to the TS
assembler, which silently dropped the non-syncing packets with no loss
counter. The only loss accounting was DiscStream's read-error zero-fill
path, so mux reported lost_video_secs=0 for decrypt-dropped content and
the abort gate accepted the rip even under abort_on_lost_secs=0. A rip
missing real video/audio segments was published as a perfect success.

decrypt_sectors now returns the number of bytes in scrambled units that
no key could decrypt. DecryptingSectorSource accumulates that into a
shared counter exposed via decrypt_loss(); both mux pipelines fold it
into lost_bytes() — the inline DiscStream path directly, and the
file-backed highway via PipelinedPesStream sharing the producer's
counter. Restore-to-original is unchanged, so clear nav-files are never
corrupted; metadata-probe callers that don't read the counter are
unaffected. Adds regression tests at the decrypt and decorator layers.

src/mux/disc.rs

@@ -811,7 +811,17 @@ impl crate::pes::Stream for DiscStream {
     }
 
     fn lost_bytes(&self) -> u64 {
-        self.lost_bytes
+        // Read-error zero-fill loss (counted in fill_extents) PLUS decrypt-time
+        // loss — bytes of scrambled AACS units the decorator could not decrypt
+        // and passed through still encrypted (the TS assembler silently drops
+        // them). Both are real missing content the abort gate must see; without
+        // the decrypt term a partial key failure reports lost_bytes=0 and a rip
+        // missing segments passes even under abort_on_lost_secs=0.
+        self.lost_bytes.saturating_add(
+            self.reader
+                .decrypt_loss()
+                .load(std::sync::atomic::Ordering::Relaxed),
+        )
     }
 }