Start super super simple... Is the slave cylinder down on the transmission external? Like can you actually see it? If so, crawl under and have someone push on the clutch while you're looking at the slave. Does the rod move? If not, that narrows it down to your master cylinder, your clutch line or your slave. If the slave is internal in the bell housing, look around and see if there any type of inspection plug or window that you can get a view inside the bellhousing without actually pulling. Basically try to get your eyes on the slave and see if it's moving.
My guess is it's not going to be moving. The squeeling noise is interesting though.
Now if it is moving, then you need to figure out if it's moving enough. I'd hit up the YJ section and simply ask how much throw that shaft should have... If it all checks out, transmission is coming out next cause there's a throwout or clutch itself issue.
That squeeling noise keeps me wondering though, if it was a recent job, could the clips or whatever that hold the throwout bearing in place possibly have come loose, maybe just one side?
Talking out loud there for others to run with...
The fact you've got bubbles though makes me think it's something slave/master/line related. Your method of bleeding it RARELY works. I'd try to get your hands on a vacuum bleeder. They're cheap at harbor freight or if you have a ride to 95 & trop area of town I'd let you borrow mine. Harbor freight is probably closer though and I don't think they're more then $20 for a hand pump one. That would be my very first thing to do on the system if the rod isn't moving. Make 100% sure it's bled with no air in the system. If it still doesn't work, look for visual signs of leaking. If nothing there... Then it's likely your slave cylinder. Could be master but like said above, I'd lean to the slave as well...