refactor: make components resuable for chat llm (#202)

.changeset/cool-jeans-bake.md

templates/components/engines/typescript/agent/chat.ts

templates/components/engines/typescript/chat/chat.ts

...es/components/llamaindex/typescript/documents/pipeline.ts

...ates/components/llamaindex/typescript/documents/upload.ts

templates/components/vectordbs/typescript/milvus/shared.ts

...reaming/express/src/controllers/chat-upload.controller.ts

...lates/types/streaming/nextjs/app/api/chat/upload/route.ts

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

...streaming/nextjs/app/components/ui/chat/hooks/use-file.ts