When my hens went through molts and just looked and felt poor in general, I gave them a boost of protein every night. I wet their regular food down into a mash, sometimes with an electrolyte solution, added in a raw egg with the shell and some canned chicken. Nice and bland but packed full of...
I’m so sorry about your hen. They have such short lives but steal so much of our hearts. It sounds like you have given her a great life full of much love and care.