* whisper : improve whisper-cli executable path detection in model download shell scripts
If whisper-cli is found on the path, do not suggest invoking from build directory. This improves flexibility and usability for distribution and packaging scenarios.
* whisper : enhance Windows model download batch script to have comparable functionality and behaviour as shell scripts
* Download models to the current directory if the script is executed from the \bin\ directory (for future distribution scenarios where the script is in the \bin\ subdirectory of a Windows build)
* Add model_path command line argument
* If whisper-cli is found on the path, do not suggest invoking from build directory
* whisper : resolve compiler warning by removing duplicate definition of NOMINMAX in whisper-cli code
This change ensures that when the script is packaged and distributed, models are downloaded to the current directory instead of the script's location, preventing conflicts with system directories. This improves flexibility and usability for distribution and packaging scenarios.