## What
- Add Replicate as a chat provider backed by the documented predictions
API
- Register Replicate in the Go model factory and provider config
- Support non-streaming chat through sync predictions, polling fallback,
streaming through `urls.stream`, model listing, and connection checks
## Notes
- Uses `POST /v1/predictions` with Replicate model identifiers in
`version`, which supports official and community model identifiers
- Maps RAGFlow messages into Replicate prompt-shaped inputs (`prompt`,
optional `system_prompt`) and forwards common documented LLM inputs:
`max_new_tokens`, `temperature`, `top_p`
- Preserves whitespace in SSE output chunks and emits RAGFlow `[DONE]`
at stream completion
## Tests
- `go test -vet=off -run TestReplicate -count=1
./internal/entity/models`
- `go test -vet=off -count=1 ./internal/entity/models`
Refs #14736
4c9529ef36