refactor(app): remove scaffold and migrate input styles

src/app/chat/components/__tests__/tailwind-components.test.tsx

@@ -3,6 +3,7 @@ import { describe, expect, it, vi } from "vitest";
 
 import { ChatHeader } from "../chat-header";
 import { ChatInsufficientCreditsBanner } from "../chat-insufficient-credits-banner";
+import { ChatInputTextField } from "../chat-input-text-field";
 import { ChatSendButton } from "../chat-send-button";
 import { ImageBubble } from "../image-bubble";
 import { MessageAvatar } from "../message-avatar";
@@ -160,4 +161,24 @@ describe("chat Tailwind components", () => {
     expect(memberHtml).toContain("bg-[rgba(13,11,20,0.7)]");
     expect(memberHtml).toContain("size-[var(--icon-size-xl,32px)]");
   });
+
+  it("renders ChatInputTextField with textarea utilities", () => {
+    const html = renderToStaticMarkup(
+      <ChatInputTextField
+        value="Hello"
+        onChange={() => undefined}
+        onSubmit={() => undefined}
+        placeholder="Message Elio"
+      />,
+    );
+
+    expect(html).toContain("<textarea");
+    expect(html).toContain('aria-label="Message"');
+    expect(html).toContain("min-h-[var(--chat-send-button-size,40px)]");
+    expect(html).toContain("max-h-[min(30vh,120px)]");
+    expect(html).toContain("caret-[var(--color-accent,#f84d96)]");
+    expect(html).toContain("placeholder:text-[var(--color-text-hint,#757575)]");
+    expect(html).toContain("Message Elio");
+    expect(html).toContain("Hello");
+  });
 });