[feat]: Should be able to pass `keepMounted` to DialogPortal

[arsmth]

Feature description

It is currently not possible when using base-ui to pass the keepMounted prop to the <DialogPortal>.

My current solution and suggestion is to add the prop to the DialogContent component:

   function DialogContent({
     className,
     children,
     showCloseButton = true,
+    keepMounted = false,
     ...props
   }: DialogPrimitive.Popup.Props & {
     showCloseButton?: boolean;
+    keepMounted?: boolean;
   }) {
     return (
-      <DialogPortal keepMounted={keepMounted}>
+      <DialogPortal keepMounted={keepMounted}>
         <DialogOverlay />
         <DialogPrimitive.Popup
         // ...

Link to the relevant Base UI docs for context:
https://base-ui.com/react/components/dialog#portal

Affected component/components

Dialog

Additional Context

Additional details here...

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• I've made research efforts and searched the documentation
• I've searched for existing issues and PRs