Front brake on driver side sticking

The best way to find this is to get the brake to lock up again, then open the hydraulic circuit at various places to determine where the brake fluid is getting trapped. My guess is you can open the bleeder screw on the caliper and the brake will release, and you can loosen the line at the master cylinder and it will not release. If that's what you find, use a large channel-lock pliers to peel open the metal bracket where it's crimped around the center of the rubber flex hose. If rust has built up inside that crimp, it will constrict the hose. You'll be able to force brake fluid under pressure through the restriction, but it won't be able to flow back freely. The brake will drag and heat up, and that will cause the fluid to expand and apply the brake even harder.