This change modifies `load_dotenv_for_agent` to first capture the environment variables already set in the process. After loading the `.env` file with `override=True`, it restores the values of these initially set variables, ensuring that explicitly set environment variables are not overwritten by the `.env` file. A new environment variable, `ADK_DISABLE_LOAD_DOTENV`, is also introduced to completely skip the `.env` loading process
Close#4020
Close $4018
Co-authored-by: George Weale <gweale@google.com>
PiperOrigin-RevId: 852981654
George WealeandCopybara-Service