Allow floating reroute switches (#862)

- Resolves https://github.com/Comfy-Org/ComfyUI_frontend/issues/3247

Bypasses the logic that automatically removed reroutes that had no
remaining links. Reroutes are now always converted to floating whenever
reroutes are reconnected.

src/canvas/ToInputRenderLink.ts

@@ -65,6 +65,8 @@ export class ToInputRenderLink implements RenderLink {
     // Set the parentId of the reroute we dropped on, to the reroute we dragged from
     reroute.parentId = fromReroute?.id
 
+    // Keep reroutes when disconnecting the original link
+    existingLink.disconnect(this.network, "output")
     const newLink = outputNode.connectSlots(fromSlot, inputNode, input, existingLink.parentId)
 
     // Connecting from the final reroute of a floating reroute chain