fix(venue-crowd): generation-gate stinger handlers; recrop on video size change

Codex preflight round 5: (1) an ended/timeout handler orphaned by stop()
could fire into a later stinger's lifecycle on the reused element — handlers
now detach unconditionally and carry a generation token; (2) the renderer
only re-applied cover-crop on camera aspect changes, so a src swap with a
different intrinsic size kept stale repeat/offset — it now recrops when
videoWidth/Height change.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

plugins/highway_3d/screen.js

@@ -3489,6 +3489,16 @@
                         // videoWidth === 0 until metadata lands — showing the
                         // plane before that paints a black flash over the plate.
                         const ready = !!el && el.videoWidth > 0;
+                        // venue-crowd.js swaps src on the same element (loop ↔
+                        // stinger); a new intrinsic size needs a fresh
+                        // cover-crop, which _bgFitBackdropPlane only reapplies
+                        // on camera aspect changes.
+                        if (ready && (layer.lastVidW !== el.videoWidth ||
+                                      layer.lastVidH !== el.videoHeight)) {
+                            layer.lastVidW = el.videoWidth;
+                            layer.lastVidH = el.videoHeight;
+                            layer.applyCoverCrop();
+                        }
                         const opacity = i === 0 ? 1 - _venueCrowdMix : _venueCrowdMix;
                         layer.mat.opacity = opacity;
                         layer.mesh.visible = ready && opacity > 0.01;

static/v3/venue-crowd.js

@@ -110,6 +110,7 @@
     let _loadingLoop = null;    // loop currently waiting on canplaythrough
     let _fadingLoop = null;     // loop currently crossfading in (not yet active)
     let _stingerUntilEnded = false;
+    let _stingerGen = 0;        // identity for ended/timeout handlers
     let _lastStingerAt = -Infinity;
     let _prevStreak = 0;
     let _lastAccuracyPct = null; // from perf events; stats:recorded carries none
@@ -276,10 +277,15 @@
             _pendingLoop = null;
             showLoop(pending, FADE_MS);
         };
+        const myGen = ++_stingerGen;
         const back = () => {
-            if (!_stingerUntilEnded) return;
+            // Always detach: a handler left behind by a stop()/manifest swap
-            _stingerUntilEnded = false;
+            // must not fire into a LATER stinger's lifecycle on this reused
+            // element (the gen check below guards that; the boolean alone
+            // would pass once a new stinger is active).
             video.removeEventListener('ended', back);
+            if (_stingerGen !== myGen || !_stingerUntilEnded) return;
+            _stingerUntilEnded = false;
             // Fade back to the loop layer (which kept playing underneath).
             fadeMixTo(_activeLayer === 1 ? 1 : 0, STINGER_FADE_MS);
             flushPending();
@@ -344,6 +350,7 @@
     function stop() {
         cancelFade();
         _stopGen++;
+        _stingerGen++;
         _stingerUntilEnded = false;
         _pendingLoop = null;
         _loadingLoop = null;