Oh OP that all sounds really stressful for you!
First of all, yes babies do have periods when they are more distracted and they also get periods where they feed more and wake more at night. This will pass, no matter what you do. Maybe in spite of whatever you do.
Secondly, I think try to relax if you can and keep it simple. Your baby is still very young for weaning (I know a doctor has advised it) so milk should absolutely be the primary form of food. Solid food is just for learning about at this point.
Thirdly, i would offer both breasts as per normal. Don’t restrict to just one as this might affect your supply. The fore and hind milk thing is a bit misleading so try not to worry about that!
In terms of getting baby to focus, I would recommend trying some skin to skin. Go into a quiet part of the house, maybe even lie down together. Don’t look at your phone (annoying I know) and just do some skin to skin cuddles and see if she will feed.
I would also wait until she is hungry or asking for a feed. Babies at this age can be really efficient at getting milk so they can feed quickly compared to when they were tiny. Keep an eye on her nappies and weight gain but if that’s tracking normally then she will be getting enough.
It is so hard when they suddenly start waking up at night. Is it possible that her tummy is full because of the baby rice and uncomfortable but she still wants to feed so she keeps waking up to try? Is the baby rice helping with the reflux?
Babies do go through sleep regressions like you are describing and sometimes we can’t figure out why at all. Being kind and gentle and feeding her for comfort when she asks is the best you can do. I promise it will all change again very soon, even if it feels like you will never sleep again! When my son suddenly started waking (and feeding) throughout the night I started watching a long drama on Netflix (on silent with subtitles) so I actually looked forward to when he woke up. Even though I was a zombie. It meant I didn’t feel so resentful of him.
Anyway sorry that was very long winded but hopefully helpful. I have had 3 babies, all EBF and can definitely relate to what you are going through!