fix(playground): stop streaming chat bubbles from pulsing

The streaming-message bubble in the smart-dashboard chat drawer used
`animate-pulse` while tokens arrived. The constant fade in/out reads
as visual noise when the agent is mid-stream — especially with longer
replies where it pulses for many seconds. Drop the animation; the
ellipsis placeholder still communicates the loading state for empty
streaming bubbles.

Author: MarioCadenas

apps/dev-playground/client/src/features/smart-dashboard/components/chat-drawer.tsx

@@ -239,7 +239,7 @@ function MessageBubble({ message }: { message: ChatMessage }) {
           isUser
             ? "bg-primary text-primary-foreground rounded-br-sm"
             : "bg-muted text-foreground rounded-bl-sm"
-        } ${message.streaming ? "animate-pulse" : ""}`}
+        }`}
       >
         {message.content || (message.streaming ? "…" : "")}
       </div>