A list of relative paths of files to import into the pacz.
Combining these with Phoenix.BuilderUIClient.UserFriendlyBuilderSessionInitialization.FilesToCopyBaseDir should yield the full paths to the actual files to copy.
No relative paths in this list should traverse up a directory.
This field is only meaningful if Phoenix.BuilderUIClient.UserFriendlyBuilderSessionInitialization.Mode is Phoenix.BuilderUIClient.UserFriendlyBuilderSessionInitialization.InitializationOption.IMPORT_FILES.
Otherwise, it may be null, and should be ignored.
