I live in Riverside, California (halfway between Los Angeles and Palm
Springs).

My house is 35 years old.

Six or seven times during this period, I've applied UN-DILUTED Muriatic
Acid to clean the concrete slab on my patio. Now the slab is now very
rough (it hurts to walk on with bare feet).

Although I can't pour another thick layer of concrete over the existing
slab, can I apply a thin overlay to cover the old, dirty, stained and
pitted concrete to result in a smoother and good-looking slab?

Can a fairly-knowledgeable homeowner do this project?
What product(s) are needed?
What steps are involved?
How durable is the overlay? (The concrete slab is hosed off several
times a week to remove leaves and dirt. Also, the patio is surrounded
by flower beds, potted plants are on the slab and hanging pots are
above the patio. All get watered several times a week).