v2 message format and upgrade to ai sdk v5 (#743)

Co-authored-by: GitHub Action <action@github.com>
Co-authored-by: Liang-Shih Lin <liangshihlin@proton.me>
Co-authored-by: Dominik Engelhardt <dominikengelhardt@ymail.com>
Co-authored-by: Jay V <air@live.ca>
Co-authored-by: adamdottv <2363879+adamdottv@users.noreply.github.com>

sst-env.d.ts

@@ -5,20 +5,20 @@
 
 declare module "sst" {
   export interface Resource {
-    "Api": {
-      "type": "sst.cloudflare.Worker"
-      "url": string
+    Api: {
+      type: "sst.cloudflare.Worker"
+      url: string
     }
-    "Bucket": {
-      "type": "sst.cloudflare.Bucket"
+    Bucket: {
+      type: "sst.cloudflare.Bucket"
     }
-    "Web": {
-      "type": "sst.cloudflare.Astro"
-      "url": string
+    Web: {
+      type: "sst.cloudflare.Astro"
+      url: string
     }
   }
 }
 /// <reference path="sst-env.d.ts" />
 
 import "sst"
-export {}
+export {}