Rewrite osxmetadata to use native Objective-C methods where possible

[RhetTbull]

Reference this. Also, see #10 and #61.

[RhetTbull]

Tags can be set like this:

""""Set Finder tags on files and folders."""

import sys

from Foundation import NSURL, NSURLTagNamesKey, NSURLLocalizedLabelKey

if __name__ == "__main__":
    file = sys.argv[1]
    tags = sys.argv[2:]
    tags = ["Tag5\n5"]
    url = NSURL.fileURLWithPath_(file)
    if not url.setResourceValues_error_(dict(NSURLTagNamesKey=tags), None):
        print(f"Error setting tags {tags} on {file}")
        sys.exit(1)
    print(f"Tags {tags} set on {file}")
    label_name = url.getResourceValue_forKey_error_(None, NSURLLocalizedLabelKey, None)
    print(f"Label name: {label_name}")

[RhetTbull]

Reference: https://github.com/hugocornejo/Locker-Room/blob/cbe8788ef1216be22b1cf7d2efc42b49f61ac7ed/DribbbleLikeDownloader.m

-(void)setFinderComment:(NSString*)comment forFile:(NSString*)path
{
	@try {
		static FinderApplication *finderApp = nil;
		if (finderApp == nil) {
			finderApp = [SBApplication applicationWithBundleIdentifier:@"com.apple.finder"];
		}
		NSURL *location = [NSURL fileURLWithPath:path];
		FinderItem *item = [[finderApp items] objectAtLocation:location];
		item.comment = comment;
	}
	@catch (NSException *ex) {
		NSLog(@"Unable to set finder comment for %@: %@", path, ex);
	}
}

This still involves scripting but uses direct communication with Finder instead of calling AppleScript.