Namek
Window-Null blinked beside the saddened AI, and placed a hand on the hologram's right shoulder. Techinically they are not touching, but - having collected numerous data of many experiences regarding emotional states - he calculated the approximate point of impact, placed his hand there, and attempted to pass on a feeling of comfort. To the Library AI, he seems... far more advanced than she is - probably due to the fact that his processors or whatever he uses is on a relatively gigantic ship, while all she has now is the satellite.
"Answer: Negative. 1,481 years since your permanent assignment is an excellent run. Had your creators not created you, the Library would not have lasted so long."
He looked on to what remains of the planet. "Reassurance: The library may be gone now, but I had the sensibility to preserve all the information I could, in my own, vast databanks stored with the Core. The data it used to hold is still safe. It just so happens that I was built with a similar purpose to you, but at a much larger scale - perhaps unfathomably larger than... Correction: unfathomable now, as you had lost access to the information that could unlock a better understanding, but allow me to show you..."
A file was transferred to the databanks of the Library AI... it was one of her own books! A book on trans-dimensional factions. It was only a snippet of a part of the book, but the part that this AI had chosen... the "Dimensional Collective," it is familiar to her. In fact, in the Class Primer section, it shows that the very same AI - literally named Window-Null - is the head of the 'Explorer-Class,' a section of the Collective that is dedicated to information gathering, scouting and preservation of knowledge. The AI beside her is the leader of an entire network of librarians, among other things related to knowledge and information sciences.
"I have come to offer closure. I cannot save you - as noble as you are, your time has unfortunately come to an end. However, I can give you peace - knowledge of the fact that I will continue guarding the information in your stead, as it is literally my duty to do so for every ounce of knowledge the Collective finds."
He then turns to the AI, his singular eye emboldened with purpose. "As for the problem of who killed your planet - and your library... The Collective are looking into the problem. This is but the first step in the solution. You have my word that we will do our best to stop them."
"...Curious: is there any last requests you may happen to have?"