feat: add multi-modal (file upload) and model selection to create-llama

create-app.ts

index.ts

templates/components/ui/shadcn/chat/chat-input.tsx

templates/components/ui/shadcn/chat/chat.interface.ts

templates/components/ui/shadcn/file-uploader.tsx

templates/components/ui/shadcn/upload-image-preview.tsx

templates/index.ts

templates/types.ts

templates/types/streaming/nextjs/app/api/chat/route.ts

...es/types/streaming/nextjs/app/components/chat-section.tsx

...es/streaming/nextjs/app/components/ui/chat/chat-input.tsx

templates/types/streaming/nextjs/constants.ts

templates/types/streaming/nextjs/package.json