start with activity + fix tests

src/model/user/basic.rs

@@ -1,12 +1,25 @@
 // TODO: put back in `src/model/user/mod.rs` once that is cleaned up
 
 use super::{AllowedToEditPaymentStatusUser, ManageUserUser, User};
-use crate::model::{family::Family, log::Log, mail::valid_mails, role::Role};
+use crate::model::{activity::Activity, family::Family, log::Log, mail::valid_mails, role::Role};
 use chrono::NaiveDate;
 use rocket::{fs::TempFile, tokio::io::AsyncReadExt};
 use sqlx::SqlitePool;
 
 impl User {
+    pub(crate) async fn add_note(
+        &self,
+        db: &SqlitePool,
+        updated_by: &ManageUserUser,
+        note: &str,
+    ) -> Result<(), String> {
+        let note = note.trim();
+
+        Activity::create(db, note, "relevant_for", None).await;
+
+        Ok(())
+    }
+
     pub(crate) async fn update_mail(
         &self,
         db: &SqlitePool,