So I've read that ammonia based cleaners will destroy a chrome lined barrel. But what will it do to nitride?

It wont
Following the directions will help prevent this

ETA
Something i do that i dont see mentioned elsewhere is, if i have a max of 10 minutes of allowance for the solvent to sit inside. I will do my last dry pass through at minute 7ish and get a sopping wet patch of regular bore cleaner down the pipe. By minute 10 im already into the final dry passes before it gets put away. Main thought was diluting any remaining presence of it and removing it with the cleaner after it did its thing.

Its safe on both. I wouldn't let it sit too long.
Then flush with Gunscrubber and a wet patch of CLP followed by a dry one.

There is no "time limit" as mentioned in the directions. Most ammonia based cleaners have about 5% inside of it. Hoppes don't have a number but it is supposedly less than 10% way more than what Sweet's claim to have. Yet I haven't heard of anyone taking a very long time to clean out their barrels. Keep in mind the ammonia content goes down as the liquid sits.

You can do an at home test. Take a piece of metal, a control one of the same time, and pour some of the ammonia based cleaner on it and leave it. See what happens. My guess is not much.

Personally I wouldn't use something with such doubts when there are so many better things out there. Boretech, WipeOut, etc all are really good stuff that works.

OP just call the company who makes the cleaning agent you are looking at buying and ask them so that you get the answer you want.  I have personally done that before and I will in the future if I have a question like that because the last thing I want to do is go by someone else's word and damage a barrel of mine.  The manufacturer will tell you if they are worth their salt.

I switched to Wipe Out, Patch Out

Works better with no ammonia

Afaik between KG12, modern spartan system copper destroyer, and sweets, none have any effect on steel.

Don't worry about it.

Just follow the directions and you're GTG.  Many of the cleaners strip all oil from the bore, leaving no protection.  Run a wet patch or two, and then a dry one.