all: fix golangci-lint issues (#3064)

hscontrol/state/state.go

@@ -230,6 +230,7 @@ func (s *State) ReloadPolicy() ([]change.Change, error) {
 	// propagate correctly when switching between policy types.
 	s.nodeStore.RebuildPeerMaps()
 
+	//nolint:prealloc // cs starts with one element and may grow
 	cs := []change.Change{change.PolicyChange()}
 
 	// Always call autoApproveNodes during policy reload, regardless of whether
@@ -260,7 +261,7 @@ func (s *State) ReloadPolicy() ([]change.Change, error) {
 // CreateUser creates a new user and updates the policy manager.
 // Returns the created user, change set, and any error.
 func (s *State) CreateUser(user types.User) (*types.User, change.Change, error) {
-	if err := s.db.DB.Save(&user).Error; err != nil {
+	if err := s.db.DB.Save(&user).Error; err != nil { //nolint:noinlineerr
 		return nil, change.Change{}, fmt.Errorf("creating user: %w", err)
 	}
 
@@ -294,7 +295,7 @@ func (s *State) UpdateUser(userID types.UserID, updateFn func(*types.User) error
 			return nil, err
 		}
 
-		if err := updateFn(user); err != nil {
+		if err := updateFn(user); err != nil { //nolint:noinlineerr
 			return nil, err
 		}
 
@@ -512,7 +513,7 @@ func (s *State) Disconnect(id types.NodeID) ([]change.Change, error) {
 	})
 
 	if !ok {
-		return nil, fmt.Errorf("node not found: %d", id)
+		return nil, fmt.Errorf("%w: %d", ErrNodeNotFound, id)
 	}
 
 	log.Info().EmbedObject(node).Msg("node disconnected")
@@ -765,7 +766,7 @@ func (s *State) RenameNode(nodeID types.NodeID, newName string) (types.NodeView,
 
 	// Check name uniqueness against NodeStore
 	allNodes := s.nodeStore.ListNodes()
-	for i := 0; i < allNodes.Len(); i++ {
+	for i := range allNodes.Len() {
 		node := allNodes.At(i)
 		if node.ID() != nodeID && node.AsStruct().GivenName == newName {
 			return types.NodeView{}, change.Change{}, fmt.Errorf("%w: %s", ErrNodeNameNotUnique, newName)
@@ -832,7 +833,7 @@ func (s *State) ExpireExpiredNodes(lastCheck time.Time) (time.Time, []change.Cha
 
 	var updates []change.Change
 
-	for _, node := range s.nodeStore.ListNodes().All() {
+	for _, node := range s.nodeStore.ListNodes().All() { //nolint:unqueryvet // NodeStore.ListNodes not a SQL query
 		if !node.Valid() {
 			continue
 		}
@@ -1850,7 +1851,7 @@ func (s *State) HandleNodeFromPreAuthKey(
 				}
 			}
 
-			return nil, nil
+			return nil, nil //nolint:nilnil // intentional: transaction success
 		})
 		if err != nil {
 			return types.NodeView{}, change.Change{}, fmt.Errorf("writing node to database: %w", err)