I'm posting this with a grain of salt, but according to the data-miners, denying quests does not affect friendship (although it says it does in the official guide. There are other inconsistencies in the official guide as well).
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Anecdotally, I've noticed villager dialogue is typically positive and in good spirits when I deny a quest. I always took the chime sound just as an indication the task/interaction was finished, but I don't know that for sure, I've just been referring to the datamines.
I have had villagers sometimes get upset when I don't let them buy something out of my pockets. Occasionally, there will even be an "are you sure" dialogue where they really want you to sell it to them. I haven't seen any data on those interactions.