Calculate the name of the result file for a given image name.

contains checks if a string is in a slice.

Helper function to compare slices as reflect.DeepEqual can be overkill for simple string slices.

GetEnv retrieves an environment variable or returns a default value.

GetEnvAsInt gets an environment variable as an integer, with a fallback default value.

GetFileSize returns the size of the file at the given path in bytes.

ImageToFilename transforms a Docker image name into a file system-friendly filename.

SanitizeImageName replaces slashes and colons in the image name with underscores.