Form I-485

I had a domestic violence charge that got dismissed in pre-trial.

Soon after the incident occurred my attorney asked me to get 4-5 anger management classes as that would increase the chances of my case getting dismissed but said the court never asked/mandated the classes.

And he also said the prosecutor elected to dismiss the case due to lack of evidence and because he was satisfied that I completed anger management counseling sessions.

I've a few questions around this:

1) When I apply for I-485, will this situation be treated as Conviction by Immig Officer thouse the case was dismissed in pre-trial?

2) Can I be deported for this when I file for I-485? Am I risking by applying for I-485?

3) The court did not give a separate disposition letter (disposition is in the Criminal Complaint itself). We drafted a letter explaining the charges against me and the outcome of the case and took stamp, seal along with Clerk's signature from the court.

When I file my 485 will this letter be enough as a proof to the Immig Officer that my case was dismissed?
Or do I need to submit the entire docket?