Revert "feat: Transitions, spacing, scroll fade, prompt area update (#11168)" (#11461)

Co-authored-by: adamelmore <2363879+adamdottv@users.noreply.github.com>

packages/ui/src/components/message-part.tsx

@@ -49,7 +49,6 @@ import { Tooltip } from "./tooltip"
 import { IconButton } from "./icon-button"
 import { createAutoScroll } from "../hooks"
 import { createResizeObserver } from "@solid-primitives/resize-observer"
-import { MorphChevron } from "./morph-chevron"
 
 interface Diagnostic {
   range: {
@@ -416,7 +415,7 @@ export function UserMessageDisplay(props: { message: UserMessage; parts: PartTyp
               toggleExpanded()
             }}
           >
-            <MorphChevron expanded={expanded()} />
+            <Icon name="chevron-down" size="small" />
           </button>
           <div data-slot="user-message-copy-wrapper">
             <Tooltip