fix: emoji picker uses full panel width with no dead space

Remove width: 100% !important override that fought emoji-mart's shadow
DOM grid. Container now uses w-fit to wrap content tightly. GIF picker
gets explicit w-[390px] to maintain its own width independently.

packages/web/src/components/chat/GifPicker.tsx

@@ -79,7 +79,7 @@ export function GifPicker({ onGifSelect }: GifPickerProps) {
   };
 
   return (
-    <div className="flex flex-col h-[390px]" onKeyDown={handleKeyDown}>
+    <div className="flex flex-col h-[390px] w-[390px]" onKeyDown={handleKeyDown}>
       {/* Search */}
       <div className="px-3 pt-2 pb-1.5">
         <input