feat: integrate user profile pictures with circular avatar display and upload in settings

frontend/src/lib/api.ts

@@ -163,6 +163,7 @@ export const api = {
     displayName?: string;
     email?: string;
     password?: string;
+    avatarUrl?: string;
     alarmChannels?: string[];
     alarmEmail?: string;
     discordWebhookUrl?: string;