plea bargain
A plea bargain is one type of deal made between prosecutor and defense attorney.
A special prosecutor would be appointed. It is normally a prosecutor from a neighboring area, or an experienced defense attorney.
Judge, Prosecutor, and Defense Attorney
No.
There is no "presiding officer" at a plea negotiation - only the prosecutor and the defense attorney. As a matter of little known fact, although most judges DO go along with a negotiated plea deal, the judge in the case is not required to abide by the plea bargain agreement and can reverse or change the parameters of the plea deal.
what are all the procedlural and substantive ways that a prosecutor and a defense attorney can resolve a case before it goes to a grand jury.
I believe it is one who prosecutes, hence prosecutor.
Exculpatory evidence
No.
If the client is guilty then the defence attorney should get the least sentence possible
The state prosecutes its case and the defence then answers.
From the government side it would be the prosecutor. On the other side it would be a a defense attorney.