Gemini LLM backend using the REST API via Req.
Configuration
# config/config.exs
config :adk, :gemini_api_key, "your-api-key"
# Or via environment variable
GEMINI_API_KEY=your-api-keyUsage
config :adk, :llm_backend, ADK.LLM.Gemini
# Or call directly
ADK.LLM.Gemini.generate("gemini-flash-latest", %{
instruction: "You are helpful.",
messages: [%{role: :user, parts: [%{text: "Hello"}]}]
})