For further clarification, typically the seeds would be started in either a rapid rooter or liner containing a soil-less mix. In my experience certain types of mold/grain mites can decimate a seedling before the cotyledon has time to emerge. They also can spread fungal diseases to the plant early on that can sometimes be too much to overcome. For this reason I use rapid rooter or root riot style cubes for high value seeds that cannot be replaced. For things like F2s the really small agricultural liners with a soil-less mix work just fine for me, only the strong survive kind of scenario. These are only slightly larger than a rapid rooter. By the time they are in need of transplant they can go in their final pot and either flip or a week of veg and flip.
If you’re in a living soil-less mix with a volume as little as 1GAL I’d definitely recommend doing a single stem grow with minimal to no veg, which is still kind of pushing it. Even doing this you’ll likely have to water daily and may benefit from a light mid-flower top-dress depending on how your soil is amended. If you’re doing soil-less with soluble feed you may be able to get away with more veg but I’m not qualified to speak on that definitively. Good luck!