Fix new link follows pointer until context menu closed (#968)

- Resolves https://github.com/Comfy-Org/ComfyUI_frontend/issues/3618

src/LGraphCanvas.ts

@@ -3951,7 +3951,7 @@ export class LGraphCanvas implements ConnectionColorContext {
   /** Get the target snap / highlight point in graph space */
   #getHighlightPosition(): ReadOnlyPoint {
     return LiteGraph.snaps_for_comfy
-      ? this._highlight_pos ?? this.graph_mouse
+      ? this.linkConnector.state.snapLinksPos ?? this._highlight_pos ?? this.graph_mouse
       : this.graph_mouse
   }
 
@@ -3964,7 +3964,8 @@ export class LGraphCanvas implements ConnectionColorContext {
     ctx: CanvasRenderingContext2D,
     highlightPos: ReadOnlyPoint,
   ): void {
-    if (!this._highlight_pos) return
+    const linkConnectorSnap = !!this.linkConnector.state.snapLinksPos
+    if (!this._highlight_pos && !linkConnectorSnap) return
 
     ctx.fillStyle = "#ffcc00"
     ctx.beginPath()
@@ -3982,7 +3983,7 @@ export class LGraphCanvas implements ConnectionColorContext {
 
     const { linkConnector } = this
     const { overReroute, overWidget } = linkConnector
-    if (!LiteGraph.snap_highlights_node || !linkConnector.isConnecting) return
+    if (!LiteGraph.snap_highlights_node || !linkConnector.isConnecting || linkConnectorSnap) return
 
     // Reroute highlight
     if (overReroute) {

src/canvas/LinkConnector.ts

@@ -32,6 +32,8 @@ export interface LinkConnectorState {
   multi: boolean
   /** When `true`, existing links are being repositioned. Otherwise, new links are being created. */
   draggingExistingLinks: boolean
+  /** When set, connecting links will all snap to this position. */
+  snapLinksPos?: [number, number]
 }
 
 /** Discriminated union to simplify type narrowing. */
@@ -61,6 +63,7 @@ export class LinkConnector {
     connectingTo: undefined,
     multi: false,
     draggingExistingLinks: false,
+    snapLinksPos: undefined,
   }
 
   readonly events = new LinkConnectorEventTarget()
@@ -639,6 +642,7 @@ export class LinkConnector {
     hiddenReroutes.clear()
     state.multi = false
     state.draggingExistingLinks = false
+    state.snapLinksPos = undefined
   }
 }