Default user avatar replaced

What changed

The built-in default user avatar is no longer the pink card with a smiling face. It is now a teal user silhouette.

Why this matters to the user

Anyone who has never set an avatar sees the new image — not only fresh installs, but also existing users upgrading from an earlier build, because the default is what shows whenever the app.user.avatar preference is empty. It appears in the sidebar, on their own chat messages, and in the profile dialog. Resetting the avatar from the profile dialog also now restores this new image.

What the user should do

Nothing — automatic. A custom uploaded image or emoji avatar is untouched.

Notes for release manager

Cosmetic only; no data is migrated or lost. Worth a screenshot in the release note since existing users will notice their own avatar change without having touched any setting.