feat: Add deep research use case (Python) (#482)

.changeset/yellow-oranges-play.md

helpers/datasources.ts

helpers/types.ts

package.json

pnpm-lock.yaml

questions/simple.ts

...components/agents/python/deep_research/README-template.md

...nts/agents/python/deep_research/app/workflows/__init__.py

...nents/agents/python/deep_research/app/workflows/agents.py

...gents/python/deep_research/app/workflows/deep_research.py

...nents/agents/python/deep_research/app/workflows/models.py

...ates/components/multiagent/python/app/api/routers/chat.py

...ents/multiagent/python/app/api/routers/vercel_response.py

...ates/components/multiagent/python/app/workflows/events.py

...ng/nextjs/app/components/ui/chat/chat-message-content.tsx

...xtjs/app/components/ui/chat/custom/deep-research-card.tsx

templates/types/streaming/nextjs/package.json