feat(core): add a limit to no. of outgoing pending friend requests

crates/core/database/src/models/users/model.rs

@@ -470,6 +470,24 @@ impl User {
 
     /// Add another user as a friend
     pub async fn add_friend(&mut self, db: &Database, target: &mut User) -> Result<()> {
+        let count = self
+            .relations
+            .as_ref()
+            .map(|relations| {
+                relations
+                    .iter()
+                    .filter(|r| matches!(r.status, RelationshipStatus::Outgoing))
+                    .count()
+            })
+            .unwrap_or_default();
+
+        let config = config().await;
+        if count >= config.features.limits.default.outgoing_friend_requests {
+            return Err(create_error!(TooManyPendingFriendRequests {
+                max: config.features.limits.default.outgoing_friend_requests
+            }));
+        }
+
         match self.relationship_with(&target.id) {
             RelationshipStatus::User => Err(create_error!(NoEffect)),
             RelationshipStatus::Friend => Err(create_error!(AlreadyFriends)),