add select example with preselected item (#339)

Author: sethhorsley

app/views/docs/select.rb

@@ -31,6 +31,28 @@ def view_template
         RUBY
       end
 
+      render Docs::VisualCodeExample.new(title: "Pre-selected Item", context: self) do
+        <<~RUBY
+          Select(class: "w-56") do
+            SelectInput(value: "banana", id: "select-preselected-fruit")
+
+            SelectTrigger do
+              SelectValue(placeholder: "Select a fruit", id: "select-preselected-fruit") { "Banana" }
+            end
+
+            SelectContent(outlet_id: "select-preselected-fruit") do
+              SelectGroup do
+                SelectLabel { "Fruits" }
+                SelectItem(value: "apple") { "Apple" }
+                SelectItem(value: "orange") { "Orange" }
+                SelectItem(value: "banana") { "Banana" }
+                SelectItem(value: "watermelon") { "Watermelon" }
+              end
+            end
+          end
+        RUBY
+      end
+
       render Docs::VisualCodeExample.new(title: "Disabled", context: self) do
         <<~RUBY
           Select(class: "w-56") do