Avatars without a photo now show clean initials

People without a profile picture now appear with tidy initials instead of an awkward placeholder.

When someone had no avatar image, the interface was falling back to a literal stand-in, rendering meaningless letters like NA or ?? where a name should be. It looked broken even though nothing was.

Now, when we know someone's name, we show their initials, so Yank Carlos becomes a clean YC. When there's no name and no image at all, we show a simple neutral person icon. We also gave the header avatar a clearer, slightly larger treatment that signals it opens your account menu.

It's a small polish, but it makes every comment, vote, and profile feel a little more finished.