feat(desktop): message history

packages/ui/src/components/button.css

@@ -148,7 +148,7 @@
       padding: 0 12px 0 8px;
     }
 
-    gap: 4px;
+    gap: 8px;
 
     /* text-14-medium */
     font-family: var(--font-family-sans);

packages/ui/src/components/session-turn.tsx

@@ -81,7 +81,6 @@ export function SessionTurn(
   createResizeObserver(contentRef, () => {
     if (!scrollRef || userScrolled() || !working()) return
     requestAnimationFrame(() => {
-      if (!scrollRef) return
       scrollRef.scrollTop = scrollRef.scrollHeight
     })
   })
@@ -266,7 +265,7 @@ export function SessionTurn(
                       </div>
                     </div>
                   </div>
-                  {/* User Message (non-sticky, scrolls under sticky header) */}
+                  {/* User Message */}
                   <div data-slot="session-turn-message-content">
                     <Message message={message()} parts={parts()} />
                   </div>

packages/ui/src/styles/animations.css

@@ -5,7 +5,7 @@
 @keyframes pulse-opacity {
   0%,
   100% {
-    opacity: 0;
+    opacity: 0.4;
   }
   50% {
     opacity: 1;
@@ -18,7 +18,7 @@
     opacity: 0;
   }
   50% {
-    opacity: 0.3;
+    opacity: 0.2;
   }
 }