Pulling to the right while braking

Ok I didn't read everything.

This is my rule. It has served me well.

Replace everything in pairs.
You would not buy one new shoe, keep both sides the same.

Also, you said your pulling started after pad replacement.
You found brake fluid.

I have seen the brake lines (rubber) looped/twisted after pad install so many times. Then they rub against themselves, and blow a big rubber bubble when you use the brakes, then they will break.

If you are seeing wear on a rubber brake line, replace both of them.

Get a new caliper for the other side.

 

Absolutely this. Brake friction material will absorb brake fluid. Once that happens the correct thing to do is replace.

Before the new pads go in clean the rotor thoroughly.