WnAvatar

[josefinalliende]

Context

• The ContactAvatar widget defined in chat folder lib/ui/chat/widgets/chat_contact_avatar.dart it is actually more like a shared component, that is is used in loots of places, not only in chat screens.
• Also, it is not used only for contacts, but for groups and for the current account too, so I think that we should name it with a more generic name
• Also, there is a ProfileAvatar widget that it is only used once

Proposal 💡

• Rename ContactAvatar to WnAvatar and move it from chat to core widgets
• Check if ProfileAvatar can be removed and replaced by WnAvatar

[josefinalliende]

PS: this idea of issue came up while reviewing #487