Stop naming specific commercial discs in the AACS and codec comments

The same scrub as the previous commit, over the files it did not reach:
the variant-MKB layout notes, the 2.1 segment index observations, the
PPS-revert regressions and the playlist-twin tiebreak.

Measurements keep their numbers — "a v70 `0x2d` body = 46_100*2 + 16"
is the useful part, and the title it came from never was.

src/mux/codec/h264.rs

@@ -1168,7 +1168,7 @@ mod tests {
         );
     }
 
-    /// Regression (Fight Club bug, H.264 variant): PPS id 0 = body A (→ avcC),
+    /// Regression (the PPS revert bug, H.264 variant): PPS id 0 = body A (→ avcC),
     /// redefined to B, then switched BACK to A. A streaming decoder is on B; the
     /// revert to A == avcC must still be emitted in-band or the A-segment
     /// decodes against B.