Implement Gemini to Ragnarok

[Yuv-sue1005]

Pull Request Checklist

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PR Type

• Feature Update
  • Description: Implemented Gemini 1.5, 1.5-flash, and 2.0-flash-experimental models into the generation component of ragnarok.
  • To use this feature, you must first install the following dependancy, on top of ragnarok's normal requirements: pip install google-generativeai
  • A quick command to test it's functionality, given a retrieval results file, can be done with the following:

export GEMINI_API_KEY="insert api key"

# 1.5 flash model
python src/ragnarok/scripts/run_ragnarok.py --model_path=gemini-1.5-flash \
--topk=100 --dataset=dataset_name --retrieval_method=bm25 \
--prompt_mode=gemini --context_size=8192 --max_output_tokens=1024

# 2.0 flash experimental
python src/ragnarok/scripts/run_ragnarok.py --model_path=gemini-2.0-flash-exp \
--topk=100 --dataset=dataset_name --retrieval_method=bm25 \
--prompt_mode=gemini --context_size=8192 --max_output_tokens=1024