Indirection layer for named AI execution profiles.

Delegates get/1 to the module configured under config :langchain_prompt, :profiles_impl, MyApp.AIProfiles.

This allows applications to define their own named profiles without coupling prompt modules to a concrete profile module.

Setup

1. Create a module that implements get/1:

   defmodule MyApp.AIProfiles do
     alias LangchainPrompt.Profile
     alias LangchainPrompt.Adapters.Langchain
   
     def get(:fast) do
       %Profile{
         adapter: Langchain,
         opts: %{chat_module: LangChain.ChatModels.ChatGoogleAI, model: "gemini-2.0-flash-lite"}
       }
     end
   end

2. Configure it:

   # config/config.exs
   config :langchain_prompt, :profiles_impl, MyApp.AIProfiles
   
   # config/test.exs
   config :langchain_prompt, :profiles_impl, LangchainPrompt.Profiles.TestImpl

3. Use it in prompt modules:

   def set_profile(_assigns), do: LangchainPrompt.Profiles.get(:fast)