static boolean isJShell(Path backingFile) {
		return backingFile != null && backingFile.toString().endsWith(".jsh");
	}
Returns a <code>Builder</code> that can be used to turn this
<code>Project</code> into executable code.

@param ctx will use the given <code>BuildContext</code> to store target files
           and intermediate results
@return A <code>Builder</code>
src/main/java/dev/jbang/source/Project.java