Fix inline parameter panel causing node height growth on remount

Two issues caused nodes to grow taller each time they scrolled back
into view with onlyRenderVisibleElements:

1. InlineParameterPanel initialized contentHeight to 0 and animated
   from maxHeight:0 to the measured height on every remount. This CSS
   transition caused the ResizeObserver in BaseNode to see the panel
   growing and add its height to the node — even though the node
   already included it. Fix: when mounted with expanded=true, render
   with maxHeight:"none" (no transition) so the panel appears at full
   size instantly.

2. The ResizeObserver skip in BaseNode only caught a single observation.
   The panel settling could fire multiple times during the CSS
   transition. Fix: use a time-based suppression (300ms) that syncs the
   tracked height ref without modifying node dimensions for all
   observations during the settle window.

https://claude.ai/code/session_01MvD1n4QeXutgwUpKJuDGHa

src/components/nodes/BaseNode.tsx

@@ -81,20 +81,26 @@ export function BaseNode({
   const isAnimatingRef = useRef(false);
   const animationTimeoutRef = useRef<ReturnType<typeof setTimeout> | null>(null);
   const isInitialMountRef = useRef(true);
-  // When true, the ResizeObserver should sync trackedSettingsHeightRef without
-  // modifying node dimensions (the height is already accounted for from a
+  // When true, the ResizeObserver syncs trackedSettingsHeightRef without
+  // modifying node dimensions (height already includes the panel from a
   // previous mount before onlyRenderVisibleElements unmounted us).
-  const skipFirstObserveRef = useRef(false);
+  const suppressObserverRef = useRef(false);
+  const suppressTimerRef = useRef<ReturnType<typeof setTimeout> | null>(null);
 
   // Adjust node height when settings expand or collapse
   useLayoutEffect(() => {
     // On initial mount with settings already expanded (e.g. remount after
     // onlyRenderVisibleElements), the node height already includes the panel.
-    // Tell the ResizeObserver to sync without adding height.
+    // Suppress ResizeObserver dimension changes while the panel settles.
     if (isInitialMountRef.current) {
       isInitialMountRef.current = false;
       if (settingsExpanded && settingsPanel) {
-        skipFirstObserveRef.current = true;
+        suppressObserverRef.current = true;
+        // Allow suppression for long enough that the panel fully renders
+        suppressTimerRef.current = setTimeout(() => {
+          suppressObserverRef.current = false;
+          suppressTimerRef.current = null;
+        }, 300);
       }
       return;
     }
@@ -187,8 +193,7 @@ export function BaseNode({
 
         // On remount with settings already expanded, the node height already
         // includes the panel. Just sync the ref without modifying dimensions.
-        if (skipFirstObserveRef.current) {
-          skipFirstObserveRef.current = false;
+        if (suppressObserverRef.current) {
           trackedSettingsHeightRef.current = newPanelHeight;
           continue;
         }
@@ -231,12 +236,15 @@ export function BaseNode({
     // eslint-disable-next-line react-hooks/exhaustive-deps
   }, [settingsExpanded, settingsPanel]);
 
-  // Cleanup animation timeout on unmount
+  // Cleanup timeouts on unmount
   useLayoutEffect(() => {
     return () => {
       if (animationTimeoutRef.current) {
         clearTimeout(animationTimeoutRef.current);
       }
+      if (suppressTimerRef.current) {
+        clearTimeout(suppressTimerRef.current);
+      }
     };
   }, []);
 

src/components/nodes/InlineParameterPanel.tsx

@@ -21,10 +21,15 @@ function InlineParameterPanelInner({
 }: InlineParameterPanelProps) {
   const contentRef = useRef<HTMLDivElement>(null);
   const [contentHeight, setContentHeight] = useState(0);
+  // When mounted with expanded=true (e.g. remount after scrolling back into
+  // view), render at full height immediately instead of animating from 0.
+  const mountedExpandedRef = useRef(expanded);
 
   useEffect(() => {
     if (expanded && contentRef.current) {
       setContentHeight(contentRef.current.scrollHeight);
+      // After first measurement, future changes should animate normally
+      mountedExpandedRef.current = false;
     }
   }, [expanded, children]);
 
@@ -57,8 +62,8 @@ function InlineParameterPanelInner({
       {/* Content area — smooth height animation */}
       <div
         id={`params-${nodeId}`}
-        className="nodrag nopan nowheel bg-[#2a2a2a] overflow-hidden transition-[max-height] duration-150 ease-out rounded-b-lg"
-        style={{ maxHeight: expanded ? contentHeight : 0 }}
+        className={`nodrag nopan nowheel bg-[#2a2a2a] overflow-hidden rounded-b-lg ${mountedExpandedRef.current ? "" : "transition-[max-height] duration-150 ease-out"}`}
+        style={{ maxHeight: expanded ? (mountedExpandedRef.current ? "none" : contentHeight) : 0 }}
       >
         <div ref={contentRef} className="px-3 pt-2 pb-3 rounded-b-lg">
           {children}