feat: implement artifact tool in TS (#328)

.changeset/modern-cars-travel.md

e2e/shared/multiagent_template.spec.ts

e2e/shared/streaming_template.spec.ts

helpers/env-variables.ts

helpers/tools.ts

...mponents/engines/typescript/agent/tools/code-generator.ts

templates/components/engines/typescript/agent/tools/index.ts

...components/llamaindex/typescript/streaming/annotations.ts

...ates/components/llamaindex/typescript/streaming/events.ts

templates/types/streaming/express/index.ts

templates/types/streaming/express/package.json

...ypes/streaming/express/src/controllers/chat.controller.ts

...s/streaming/express/src/controllers/sandbox.controller.ts

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

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

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

...nextjs/app/components/ui/chat/chat-message/chat-tools.tsx

...ming/nextjs/app/components/ui/chat/chat-message/index.tsx

...streaming/nextjs/app/components/ui/chat/chat-messages.tsx

...streaming/nextjs/app/components/ui/chat/chat.interface.ts