docs: improve forms cards

docs/content/3.forms/1.input.md

@@ -26,6 +26,8 @@ props:
 
 ### Placeholder
 
+Use the `placeholder` prop to set a placeholder text.
+
 ::component-card
 ---
 baseProps:
@@ -59,15 +61,14 @@ Use the `leading` and `trailing` props to set the icon position or the `leadingI
 ---
 baseProps:
   name: 'input'
+  placeholder: 'Search...'
 props:
   icon: 'i-heroicons-magnifying-glass-20-solid'
   appearance: 'white'
   size: 'sm'
   trailing: false
-  placeholder: 'Search...'
 excludedProps:
   - icon
-  - placeholder
 ---
 ::