fix: wheel zoom behavior for LoRA Manager widgets

- Add forwardWheelToCanvas() utility for vanilla JS widgets
- Implement wheel event handling in Vue widgets (LoraCyclerWidget, LoraRandomizerWidget, LoraPoolWidget)
- Update SingleSlider and DualRangeSlider to stop event propagation after value adjustment
- Ensure consistent behavior: slider adjusts value only, other areas trigger canvas zoom
- Support pinch-to-zoom (Ctrl+wheel) and horizontal scroll forwarding

vue-widgets/src/components/shared/DualRangeSlider.vue

@@ -280,8 +280,7 @@ const onWheel = (event: WheelEvent) => {
   if (event.clientX < rootRect.left || event.clientX > rootRect.right ||
       event.clientY < rootRect.top || event.clientY > rootRect.bottom) return
 
-  event.preventDefault()
-
+  // Adjust slider values when wheeling over the slider area
   const delta = event.deltaY > 0 ? -1 : 1
   const relativeX = event.clientX - rect.left
   const rangeWidth = rect.width
@@ -320,6 +319,9 @@ const onWheel = (event: WheelEvent) => {
       }
     }
   }
+
+  // Stop propagation to prevent canvas zoom
+  event.stopPropagation()
 }
 
 const stopDrag = (event?: PointerEvent) => {

vue-widgets/src/components/shared/SingleSlider.vue

@@ -131,11 +131,13 @@ const onWheel = (event: WheelEvent) => {
   if (event.clientX < rootRect.left || event.clientX > rootRect.right ||
       event.clientY < rootRect.top || event.clientY > rootRect.bottom) return
 
-  event.preventDefault()
-
+  // Adjust slider value when wheeling over the slider area
   const delta = event.deltaY > 0 ? -1 : 1
   const newValue = snapToStep(props.value + delta * props.step)
   emit('update:value', newValue)
+
+  // Stop propagation to prevent canvas zoom
+  event.stopPropagation()
 }
 
 const stopDrag = (event?: PointerEvent) => {