Cannot connect COMBO output to compatible COMBO input through a reroute node.

When there's a node with a COMBO output which can connect fine to another node's compatible COMBO input, it will refuse to connect when it goes through a reroute node.

Note, this is exhibited in ComfyUI's normal Reroute node, though the issue was found using "Reroute (rgthree)". Hopefully the fix would be in widgetInput so all virtualnodes benefit.

The blocking code is in [widgetInputs.js#L429](https://github.com/comfyanonymous/ComfyUI/blob/da7a8df0d2582c8dc91e5afafe51300899c91392/web/extensions/core/widgetInputs.js#L429):

```js
// Check they match
const originConfig = originNode.constructor?.nodeData?.output?.[originSlot];
if (!originConfig || !isValidCombo(targetCombo, originConfig)) {
return false;
}
```

`originNode`, being the reroute, doesn't have nodeData as it's a virtual node but, further, even if it did the "config" would be dynamic, and not a common static member on the constructor.