fix(domain): from_db_str returns Result — unknown DB values are errors not silent defaults

crates/adapters/postgres/src/follow.rs

@@ -76,13 +76,18 @@ impl FollowRepository for PgFollowRepository {
         .fetch_optional(&self.pool)
         .await
         .into_domain()
-        .map(|o| o.map(|r| Follow {
-            follower_id: UserId::from_uuid(r.follower_id),
-            following_id: UserId::from_uuid(r.following_id),
-            state: FollowState::from_db_str(&r.state),
-            ap_id: r.ap_id,
-            created_at: r.created_at,
-        }))
+        .and_then(|o| {
+            o.map(|r| {
+                Ok(Follow {
+                    follower_id: UserId::from_uuid(r.follower_id),
+                    following_id: UserId::from_uuid(r.following_id),
+                    state: FollowState::from_db_str(&r.state)?,
+                    ap_id: r.ap_id,
+                    created_at: r.created_at,
+                })
+            })
+            .transpose()
+        })
     }
 
     async fn update_state(