Improve dialog box alignment and spacing for better user experience

Update `DialogHeader` to use `sm:text-start` for RTL alignment and `DialogFooter` to use `gap-2` instead of `sm:space-x-2` for improved spacing in dialog components.

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artifacts/tx-os/src/components/ui/dialog.tsx

@@ -57,7 +57,7 @@ const DialogHeader = ({
 }: React.HTMLAttributes<HTMLDivElement>) => (
   <div
     className={cn(
-      "flex flex-col space-y-1.5 text-center sm:text-left",
+      "flex flex-col space-y-1.5 text-center sm:text-start",
       className
     )}
     {...props}
@@ -71,7 +71,7 @@ const DialogFooter = ({
 }: React.HTMLAttributes<HTMLDivElement>) => (
   <div
     className={cn(
-      "flex flex-col-reverse sm:flex-row sm:justify-end sm:space-x-2",
+      "flex flex-col-reverse gap-2 sm:flex-row sm:justify-end",
       className
     )}
     {...props}