all: apply golangci-lint 2.9.0 fixes

Fix issues found by the upgraded golangci-lint:
- wsl_v5: add required whitespace in CLI files
- staticcheck SA4006: replace new(var.Field) with &localVar
  pattern since staticcheck does not recognize Go 1.26
  new(value) as a use of the variable
- staticcheck SA5011: use t.Fatal instead of t.Error for
  nil guard checks so execution stops
- unused: remove dead ptrTo helper function

hscontrol/types/change/change.go

@@ -365,11 +365,6 @@ func KeyExpiry(nodeID types.NodeID, expiry *time.Time) Change {
 	}
 }
 
-// ptrTo returns a pointer to the given value.
-func ptrTo[T any](v T) *T {
-	return new(v)
-}
-
 // High-level change constructors
 
 // NodeAdded returns a Change for when a node is added or updated.