boolean isReadOnly() {
		synchronized (fileSystem) {
			return folderItem != null && folderItem.isReadOnly();
		}
	}
Returns whether this file is explicitly marked as read-only.  This method is only supported
by the local file system and does not apply to a versioned file that is not checked-out.
A versioned file that is not checked-out will always return false, while a 
{@link DomainFileProxy} will always return true.
From a framework point of view a read-only file can never be changed.
@return true if this file is marked read-only
Ghidra/Framework/Project/src/main/java/ghidra/framework/data/GhidraFileData.java