feat: only send user message as part of request (#957)

tests/prompts/routes.ts

@@ -1,12 +1,14 @@
+import { generateUUID } from '@/lib/utils';
+
 export const TEST_PROMPTS = {
   SKY: {
-    MESSAGES: [
-      {
-        role: 'user',
-        content: 'Why is the sky blue?',
-        parts: [{ type: 'text', text: 'Why is the sky blue?' }],
-      },
-    ],
+    MESSAGE: {
+      id: generateUUID(),
+      createdAt: new Date().toISOString(),
+      role: 'user',
+      content: 'Why is the sky blue?',
+      parts: [{ type: 'text', text: 'Why is the sky blue?' }],
+    },
     OUTPUT_STREAM: [
       '0:"It\'s "',
       '0:"just "',
@@ -17,13 +19,14 @@ export const TEST_PROMPTS = {
     ],
   },
   GRASS: {
-    MESSAGES: [
-      {
-        role: 'user',
-        content: 'Why is grass green?',
-        parts: [{ type: 'text', text: 'Why is grass green?' }],
-      },
-    ],
+    MESSAGE: {
+      id: generateUUID(),
+      createdAt: new Date().toISOString(),
+      role: 'user',
+      content: 'Why is grass green?',
+      parts: [{ type: 'text', text: 'Why is grass green?' }],
+    },
+
     OUTPUT_STREAM: [
       '0:"It\'s "',
       '0:"just "',