It's not illegal to not answer, but little things like this add up. If you act courteous and calm, it de-escalates the situation.
So, the cop asked for your passenger's ID, not because she's going to drive or anything, she just requested it. You as the driver could ask your passenger, "Do you want to give the cop your ID". This puts the onus of submitting to the cops request off of you and onto your passenger. I don't know why she asked for it though.
So basically, you escalated the situation. This isn't just her, any cop would have felt the same way. Non-compliance to simple commands is related to someone who is not going to comply to other commands.
This type of statement can be construed as someone who is willing to attack a cop because they are hiding something in order to escape arrest. Why? They have an outstanding warrant, they are covering up a crime they just committed, they are in possession of something illegal, or something else that isn't legal.
Refusing to give the keys is your second non-compliant behavior.
Non-compliance is related to a person wanting to possibly escape, and if you have the keys to your car, a simple way to escape is to turn on the car and drive away.
She called for back-up because of your behavior.
That's true. But, like you said in another post, I don't know why they didn't run your personal info to see if you are licensed to drive, have an outstanding warrant and see if your car is stolen or not.
You told them you would rather fight?
Third non-compliance behavior.
Yes, if you don't sign the summons/tickets, you can be brought to the jail.
Yeah, that was kind of screwed up on the cop's part.
Your attitude was not good. You displayed a high degree of non-compliance and that is enough to justify your arrest. This will be brought up in IA investigation and in court.
Without seeing it, I don't know if your hand was close to her waist or not, while you were holding your bag.
Why did it take 8 hours, was it busy with other arrestees?
Yep, belligerent attitude.
Did you?
So, yes, the situation had problems on your part and problems on the cops' part.
Listen to your attorney. Your civil lawsuit will be separate from the IA investigation case and court case. So, if you, somehow, are able to sue the police department, you aren't getting paid in like over a year from now.