fix(25-02): enable scrolling in template gallery

- Add flex flex-col to modal container so h-full propagates correctly
- Allows overflow-y-auto to work in TemplateExplorerView content area

src/components/quickstart/WelcomeModal.tsx

@@ -76,7 +76,7 @@ export function WelcomeModal({
 
   return (
     <div className="fixed inset-0 z-[100] flex items-center justify-center bg-black/50 backdrop-blur-sm">
-      <div className="w-full max-w-4xl mx-4 bg-neutral-800 rounded-xl border border-neutral-700 shadow-2xl overflow-hidden max-h-[80vh]">
+      <div className="w-full max-w-4xl mx-4 bg-neutral-800 rounded-xl border border-neutral-700 shadow-2xl overflow-hidden max-h-[80vh] flex flex-col">
         {currentView === "initial" && (
           <QuickstartInitialView
             onSelectBlankCanvas={handleSelectBlankCanvas}