fix(db): add image column to pets table for demo pet images

Adds `image` field to pets table schema and creates migration to support storing demo pet image URLs. Resolves TypeScript error in seed.ts where image property was being referenced on insert.

Co-Authored-By: Paperclip <noreply@paperclip.ing>

packages/db/migrations/0021_pet_image.sql

@@ -0,0 +1,2 @@
+-- Add image field to pets table for demo pet image support
+ALTER TABLE "pets" ADD COLUMN "image" text;

packages/db/src/schema.ts

@@ -135,6 +135,7 @@ export const pets = pgTable("pets", {
   customFields: jsonb("custom_fields").$type<Record<string, string>>().notNull().default({}),
   photoKey: text("photo_key"),
   photoUploadedAt: timestamp("photo_uploaded_at"),
+  image: text("image"),
   createdAt: timestamp("created_at").notNull().defaultNow(),
   updatedAt: timestamp("updated_at").notNull().defaultNow(),
 });