Rework Villager Trades

Curing a zombie villager gives unlimited access to extremely unbalanced trades. With only 3 cured villagers, you can have access to ANY diamond tool/weapon/armor for just 1 emerald. It almost completely devalues finding diamond in the game.

My idea to combat this is to make villager trades more like the travelling merchant, where the trades will be random each day but still related to the profession of the villager. The diamond equipment trades should be quite rare, as should certain other trades like golden carrots from farmers and mending books from the librarians.

Villagers could still level up by making trades. Each level would give another permanent trade slot for each day starting with 1 for beginner villagers and ending with 5 when fully leveled.