Revert "feat: Persist Studio manual edits via manifest (#593)"

This reverts commit d0abe90a82.

packages/studio/src/components/nle/NLELayout.tsx

@@ -89,6 +89,7 @@ export const NLELayout = memo(function NLELayout({
     togglePlay,
     seek,
     onIframeLoad: baseOnIframeLoad,
+    refreshPlayer,
     saveSeekPosition,
   } = useTimelinePlayer();
 
@@ -102,15 +103,13 @@ export const NLELayout = memo(function NLELayout({
     usePlayerStore.getState().reset();
   }
 
-  // Save seek position before the Player component creates a new player
-  // on refreshKey change. The Player handles the actual reload via the
-  // dual-player crossfade; we just need to persist the current time.
+  // Refresh the existing iframe in place when source files change.
   const prevRefreshKeyRef = useRef(refreshKey);
   useEffect(() => {
     if (refreshKey === prevRefreshKeyRef.current) return;
     prevRefreshKeyRef.current = refreshKey;
-    saveSeekPosition();
-  }, [refreshKey, saveSeekPosition]);
+    refreshPlayer();
+  }, [refreshKey, refreshPlayer]);
 
   // Wrap onIframeLoad to also notify parent of iframe ref
   const onIframeLoad = useCallback(() => {
@@ -210,10 +209,6 @@ export const NLELayout = memo(function NLELayout({
   const currentLevel = compositionStack[compositionStack.length - 1];
   const directUrl = compositionStack.length > 1 ? currentLevel.previewUrl : undefined;
 
-  useEffect(() => {
-    onIframeRef?.(iframeRef.current);
-  }, [compositionStack.length, onIframeRef, refreshKey, iframeRef]);
-
   // Save master seek position before drilling down so we can restore it on back-navigation.
   // saveSeekPosition() sets pendingSeekRef in useTimelinePlayer which onIframeLoad reads.
   const masterSeekRef = useRef(0);

packages/studio/src/components/nle/NLEPreview.tsx

@@ -1,4 +1,4 @@
-import { memo, useRef, useState, type Ref } from "react";
+import { memo, type Ref } from "react";
 import { Player } from "../../player";
 
 interface NLEPreviewProps {
@@ -21,17 +21,6 @@ export function getPreviewPlayerKey({
   return directUrl ?? projectId;
 }
 
-/**
- * Manages the composition preview with crossfade on reload.
- *
- * When refreshKey changes, a new Player is mounted alongside the old one.
- * The old Player stays visible (opacity 1) until the new one fires onLoad,
- * at which point the old is removed. This avoids the flash that a simple
- * key-swap remount would cause.
- *
- * Uses the render-time state adjustment pattern (React-sanctioned) to detect
- * refreshKey changes — no useEffect needed.
- */
 export const NLEPreview = memo(function NLEPreview({
   projectId,
   iframeRef,
@@ -40,56 +29,22 @@ export const NLEPreview = memo(function NLEPreview({
   directUrl,
   refreshKey,
 }: NLEPreviewProps) {
-  const baseKey = getPreviewPlayerKey({ projectId, directUrl, refreshKey });
-  const prevRefreshKeyRef = useRef(refreshKey);
-  const [retiringKey, setRetiringKey] = useState<string | null>(null);
-  const retiringTimerRef = useRef<ReturnType<typeof setTimeout> | null>(null);
-
-  // Detect refreshKey change during render (React-sanctioned derived state pattern).
-  // When the key changes, the current active player becomes the retiring player
-  // and a new active player is mounted alongside it.
-  if (refreshKey !== prevRefreshKeyRef.current) {
-    const oldKey = `${baseKey}:${prevRefreshKeyRef.current ?? 0}`;
-    prevRefreshKeyRef.current = refreshKey;
-    setRetiringKey(oldKey);
-  }
-
-  const activeKey = `${baseKey}:${refreshKey ?? 0}`;
-
-  const handleNewPlayerLoad = () => {
-    onIframeLoad();
-    if (retiringTimerRef.current) clearTimeout(retiringTimerRef.current);
-    retiringTimerRef.current = setTimeout(() => {
-      setRetiringKey(null);
-      retiringTimerRef.current = null;
-    }, 160);
-  };
+  const playerKey = getPreviewPlayerKey({ projectId, directUrl, refreshKey });
 
   return (
     <div className="flex flex-col h-full min-h-0">
       <div
-        className="relative flex-1 flex items-center justify-center p-2 overflow-hidden min-h-0 outline-none focus:ring-1 focus:ring-studio-accent/40"
+        className="flex-1 flex items-center justify-center p-2 overflow-hidden min-h-0 outline-none focus:ring-1 focus:ring-studio-accent/40"
         tabIndex={0}
         aria-label="Composition preview"
       >
-        {retiringKey && (
-          <Player
-            key={retiringKey}
-            projectId={directUrl ? undefined : projectId}
-            directUrl={directUrl}
-            onLoad={() => {}}
-            portrait={portrait}
-            style={{ position: "absolute", inset: 0, zIndex: 0, opacity: 1 }}
-          />
-        )}
         <Player
-          key={activeKey}
+          key={playerKey}
           ref={iframeRef}
           projectId={directUrl ? undefined : projectId}
           directUrl={directUrl}
-          onLoad={retiringKey ? handleNewPlayerLoad : onIframeLoad}
+          onLoad={onIframeLoad}
           portrait={portrait}
-          style={retiringKey ? { position: "absolute", inset: 0, zIndex: 1 } : undefined}
         />
       </div>
     </div>