fix(canvas): 画布连线 - 修复节点拖动时双层路径叠加残影

web/src/components/canvas/canvas-connections.tsx

@@ -14,6 +14,7 @@ export const ConnectionPath = React.memo(function ConnectionPath({
     toScrollTop = 0,
     active,
     visualMode = "full",
+    hideVisual = false,
     onSelect,
     onContextMenu,
 }: {
@@ -24,6 +25,7 @@ export const ConnectionPath = React.memo(function ConnectionPath({
     toScrollTop?: number;
     active: boolean;
     visualMode?: "full" | "hover-only";
+    hideVisual?: boolean;
     onSelect: () => void;
     onContextMenu?: (event: ReactMouseEvent<SVGPathElement>) => void;
 }) {
@@ -31,12 +33,13 @@ export const ConnectionPath = React.memo(function ConnectionPath({
     const [hovered, setHovered] = useState(false);
     const { pathD, startX, startY, endX, endY } = canvasConnectionPath(connection, from, to, fromScrollTop, toScrollTop);
     const emphasized = active || hovered;
-    const showVisual = visualMode === "full" || hovered;
+    const showVisual = !hideVisual && (visualMode === "full" || hovered);
+    const showEmphasis = !hideVisual && emphasized;
     const gradientId = `canvas-flow-${connection.id.replace(/[^a-zA-Z0-9_-]/g, "")}`;
 
     return (
         <g>
-            {emphasized ? <defs>
+            {showEmphasis ? <defs>
                 <linearGradient id={gradientId} gradientUnits="userSpaceOnUse" x1={startX} y1={startY} x2={endX} y2={endY}>
                     <stop offset="0%" stopColor={theme.node.muted} stopOpacity={0.18} />
                     <stop offset="48%" stopColor={theme.accent.primary} stopOpacity={0.58} />
@@ -52,7 +55,7 @@ export const ConnectionPath = React.memo(function ConnectionPath({
             {/* 光晕：只在强调态渲染。blur 是 filter，成本随线条数量线性上升，
                 常态几十条线全开会明显掉帧，所以刻意只给悬停/选中的那一条。
                 垫在底衬描边之下，不改动常态可读性那几层。 */}
-            {emphasized ? <path
+            {showEmphasis ? <path
                 d={pathD}
                 stroke={theme.accent.primary}
                 strokeWidth="8"
@@ -123,7 +126,7 @@ export const ConnectionPath = React.memo(function ConnectionPath({
             /> : null}
             {/* 流光：一小段高亮沿路径跑。周期与虚线流动刻意不同（2.1s vs 1.25s），
                 两者错拍才像有光在走；同频会锁成一条整体平移的虚线。 */}
-            {emphasized ? <path
+            {showEmphasis ? <path
                 className="canvas-connection-comet"
                 d={pathD}
                 stroke={`url(#${gradientId}-comet)`}
@@ -136,7 +139,7 @@ export const ConnectionPath = React.memo(function ConnectionPath({
             /> : null}
         </g>
     );
-}, (previous, next) => previous.connection === next.connection && previous.from === next.from && previous.to === next.to && previous.active === next.active && previous.visualMode === next.visualMode && previous.fromScrollTop === next.fromScrollTop && previous.toScrollTop === next.toScrollTop);
+}, (previous, next) => previous.connection === next.connection && previous.from === next.from && previous.to === next.to && previous.active === next.active && previous.visualMode === next.visualMode && previous.hideVisual === next.hideVisual && previous.fromScrollTop === next.fromScrollTop && previous.toScrollTop === next.toScrollTop);
 
 export function canvasConnectionPath(connection: CanvasConnection, from: CanvasNodeData, to: CanvasNodeData, fromScrollTop = 0, toScrollTop = 0) {
     const startX = from.position.x + from.width;

web/src/pages/canvas/canvas-project-world-layers.tsx

@@ -112,6 +112,8 @@ export const CanvasProjectWorldLayers = memo(function CanvasProjectWorldLayers(p
                         toScrollTop={props.scriptScrollTopById[to.id] || 0}
                         active={props.selectedConnectionId === connection.id || props.relatedConnectionIds.has(connection.id)}
                         visualMode="hover-only"
+                        // 拖动预览由 Leafer 图形层逐帧同步；隐藏这层静态 SVG 描边，避免两套位置叠出残影。
+                        hideVisual={props.isNodeDragging}
                         onSelect={() => props.onConnectionSelect(connection.id)}
                         onContextMenu={(event) => props.onConnectionContextMenu(event, connection.id)}
                     />