I would have thought that the first substantial rain, or heavy watering, would wash that soluble ammonia away "very quickly". If you're in a hurry, water it down repeatedly and waste the nitrogen.
If you can still smell ammonia, it's too soon. Cover with plastic overnight to concentrate the fumes.
You might transplant out some hardened seedlings without watering much, and see if they look burnt in two days.
Or if you don't want to make a Science Project of it, sow 1/3 of your seeds as soon as it might be safe. If none come up, water again and wait longer before planting the rest.
More useless generalities:
Nitrogen can be actually toxic to roots in high concentrations: really toxic, not "be afraid of all chemicals" toxic.
If the soil is "live" and warm, microbes will digest that ammonia "really fast", as long as you didn't scorch the soil life with "too much ammonia".
Ammonia is also volatile. It will tend to evaporate faster if you fork the soil up and leave the surface rough, and turn it every few days.
But what is "really fast" ?
How many flushes does it take to remove whatever amount you sprayed?
Will evaporation remove "enough"?
If it were me, I would give the microbes 3-7 days to consume as much ammonia as they can. Then flush once per day until I couldn't smell much or any under a cloch or plastic film that had concentrated the fumes overnight.
Then flush at least one more time. I respect nitrogen or ammonia's ability to "burn" root hairs.
Less wasteful would be something like let it sit a few days, water medium-heavy, then test-sow some cheap seed like fall rye or whatever you have lots of, that sprouts fast, and might be as sensitive as what you WANT to plant.. If the test seed looks very happy a week later, consider it safe because that extra week means you now have even lower levels than did NOT harm seed roots.
