From the American English perspective, all three are grammatically correct. The difference is primarily on where the emphasis is being placed, and by extension, the possible additional meanings that might be inferred, without any further context. However, remember that context is everything!
The first, "Glad you have it resolved" emphasizes that the speaker ("I") is glad, and that it's because the problem is resolved. It's somewhat open as to how it got resolved. It could be because "you" solved it, or because someone or something else solved it for you.
The second, "Glad you have resolved it" emphasizes the participation of you in getting it resolved, whether by direct action or indirectly by having someone or something else take care of (resolve) it for you.
However, the difference between those first two is very subtle, and open to disagreement among native English speakers. Both are 100% grammatically correct for all meanings that either might have. Both can mean that you solved the problem, or that you had someone or something else solve the problem, or that the problem just resolved itself without any action (e.g., the drought ended because it rained).
The third, "Glad you got it resolved" is effectively the same exact meaning as the first, but using a more informal (and more common in spoken word) verb "got" instead of "have".