feat: add trusted customer service friendships

server/store/store.go

@@ -3065,6 +3065,7 @@ func validUserProfilePatch(patch types.UserProfilePatch) bool {
 }
 
 type RelationsPersistenceInterface interface {
+	AddFriendDirect(tenantID types.TenantID, userID, peerID types.Uid, now time.Time) error
 	CreateFriendRequest(tenantID types.TenantID, req *types.FriendRequest) (*types.FriendRequest, error)
 	ListFriendRequests(tenantID types.TenantID, uid types.Uid, direction, status, cursor string, limit int) ([]types.FriendRequestListItem, string, error)
 	CountPendingFriendRequests(tenantID types.TenantID, uid types.Uid) (int, error)
@@ -3153,6 +3154,41 @@ func (relationsMapper) CreateFriendRequest(tenantID types.TenantID, req *types.F
 	return tenantAdp.TenantFriendRequestCreate(tenantID, req)
 }
 
+// AddFriendDirect creates a symmetric friendship for trusted server-side
+// workflows, such as opening a customer-service conversation. It deliberately
+// does not create a friend-request record, but it still honors either user's
+// block list.
+func (relationsMapper) AddFriendDirect(tenantID types.TenantID, userID, peerID types.Uid, now time.Time) error {
+	if userID.IsZero() || peerID.IsZero() || userID == peerID {
+		return types.ErrMalformed
+	}
+	if _, err := Users.Get(tenantID, userID); err != nil {
+		return err
+	}
+	if _, err := Users.Get(tenantID, peerID); err != nil {
+		return err
+	}
+	tenantAdp, err := tenantBusinessAdapter(tenantID)
+	if err != nil {
+		return err
+	}
+	relationship, err := relationshipContext(tenantAdp, tenantID, userID, peerID, "")
+	if err != nil {
+		return err
+	}
+	if relationship.Relationship == types.RelationshipBlockedByMe || relationship.Relationship == types.RelationshipBlockedByPeer {
+		return types.ErrPermissionDenied
+	}
+	if now.IsZero() {
+		now = time.Now().UTC()
+	}
+	if err = tenantAdp.TenantFriendshipUpsertPair(tenantID, userID, peerID, userID.P2PName(peerID), now); err != nil {
+		return err
+	}
+	cacheFriendPair(tenantID, userID, peerID)
+	return nil
+}
+
 func (relationsMapper) ListFriendRequests(tenantID types.TenantID, uid types.Uid, direction, status, cursor string, limit int) ([]types.FriendRequestListItem, string, error) {
 	if uid.IsZero() {
 		return nil, "", types.ErrMalformed