fix(live): per-packet animation always 1× — decouple from VCR.speed (#1346)

VCR.speed is the inter-packet replay-gap multiplier, not a per-packet
animation cadence multiplier. Dividing the constants by VCR.speed made
LIVE mode appear instantaneous whenever a prior REPLAY had cycled to
4×/8× (the speed persists in localStorage across page loads).

Changes:
- drawAnimatedLine: stepMs = 33 (was 33 / VCR.speed)
- drawMatrixLine: DURATION_MS = 1100 (was 1100 / VCR.speed)

Inter-packet replay timing (delay = realGap / VCR.speed, line 507) is
left untouched — that is the legitimate slow-mo / fast-forward axis.

Fixes #1346

public/live.js

@@ -3231,7 +3231,7 @@
 
     const matrixGreen = '#00ff41';
     const TRAIL_LEN = Math.min(6, bytes.length);
-    const DURATION_MS = 1100 / VCR.speed;
+    const DURATION_MS = 1100; // #1346: per-packet animation is constant; VCR.speed governs INTER-packet replay gap only
     const CHAR_INTERVAL = 0.06; // spawn a char every 6% of progress
     const charMarkers = [];
     let nextCharAt = CHAR_INTERVAL;
@@ -3363,7 +3363,7 @@
         return;
       }
       const elapsed = now - lastStep;
-      const stepMs = 33 / VCR.speed;
+      const stepMs = 33; // #1346: per-packet animation cadence is constant (~30fps); VCR.speed governs INTER-packet replay gap only
       if (elapsed >= stepMs) {
         const ticks = Math.min(Math.floor(elapsed / stepMs), 4);
         lastStep = now;