Idea: Give a choice between Claude CLI and Claude API key

[mzieniukbw]

Give a choice between Claude CLI and Claude API key (using SDK) during setup / env variable.
Note: The test-pr requires Claude CLI (at the moment, but does not need to), while execute-scenarios requires Claude API key for the open interpreter (alternative: the cli could expose a http server that underneath runs every prompt through Claude CLI https://docs.openinterpreter.com/language-models/local-models/custom-endpoint )