[fix] Fix step prop scaling issue on numeric Vue widgets (#5386)

* use step2 -> step bind on slider widget

* fix: Use step2 instead of legacy step property in WidgetSlider

The WidgetSlider was using the legacy `step` property (10x input spec value)
instead of `step2` (correct input spec value). This caused input spec step
values to appear 10x larger than intended.

- Use `widget.options.step2` (correct input spec value)
- Remove fallback to `widget.options.step` (legacy 10x value)
- Both properties coexist, so step2 should always be preferred

Fixes input spec step values not being respected in Vue node sliders.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

---------

Co-authored-by: Claude <noreply@anthropic.com>

src/renderer/extensions/vueNodes/widgets/components/WidgetSlider.vue

@@ -74,9 +74,9 @@ const precision = computed(() => {
 
 // Calculate the step value based on precision or widget options
 const stepValue = computed(() => {
-  // If step is explicitly defined in options, use it
-  if (props.widget.options?.step !== undefined) {
-    return String(props.widget.options.step)
+  // Use step2 (correct input spec value) instead of step (legacy 10x value)
+  if (props.widget.options?.step2 !== undefined) {
+    return String(props.widget.options.step2)
   }
   // Otherwise, derive from precision
   if (precision.value !== undefined) {