fix(ui): use flex layout in UploadModal to fix advanced options overflow

- Converted .modal-sheet to flex flex-col to support dynamic content
- Added flex-1 min-h-0 to .modal-body to ensure proper scrolling
- Removed fixed max-height constraints that clipped expanded content

components/upload-modal.html

@@ -11,7 +11,7 @@
   <div class="bv-modal-backdrop" data-dismiss></div>
 
   <!-- Modal Container -->
-  <div class="modal-sheet max-h-modal-shell overflow-hidden" tabindex="-1">
+  <div class="modal-sheet max-h-modal-shell overflow-hidden flex flex-col" tabindex="-1">
       <!-- Top Bar (similar to video-modal) -->
       <div class="modal-header transition-transform duration-150">
         <h2 id="uploadModalTitle" class="text-xl font-bold text-text">
@@ -42,7 +42,7 @@
       </div>
 
       <!-- Form Content -->
-      <div class="modal-body space-y-6 overflow-y-auto max-h-modal-body">
+      <div class="modal-body space-y-6 overflow-y-auto flex-1 min-h-0">
         <div class="flex justify-center">
           <div
             class="inline-flex items-center rounded-full bg-panel/80 p-1 text-sm"