fix: place canvas toolbar in layout flow to prevent message overlap

components/canvas/CanvasChatPanel.tsx

@@ -3042,7 +3042,7 @@ export function CanvasChatPanel({ chatId, initialMessages = [], onClose, onOpenF
   return (
     <div className="flex flex-col h-full bg-background/50 backdrop-blur-sm relative">
       {/* Header - Minimal with Icons */}
-      <div className="absolute top-0 right-0 z-20 p-4 flex flex-col items-end gap-2">
+      <div className="z-20 ml-auto p-4 flex flex-col items-end gap-2">
         <div className="flex items-center gap-1">
           <Button 
             variant="ghost" 
@@ -3143,7 +3143,7 @@ export function CanvasChatPanel({ chatId, initialMessages = [], onClose, onOpenF
           "flex-1 p-4",
           isDetailGenerationMode && visibleMessages.length === 0
             ? "pt-10"
-            : "pt-16"
+            : "pt-4"
         )}
       >
         <div className="space-y-6 pb-24">