Clarify shared ownership of namespace views

namespaces.go

@@ -23,6 +23,10 @@ type Namespaces struct {
 // inspection are not rewritten. [Engine.ListNamespaces] and
 // [Engine.ListCollections] remain global inventories. Invalid namespace syntax
 // or a nil engine returns an error matching ErrInvalidConfig.
+//
+// The view shares the receiver's captured configuration, clients, backend-capacity
+// pools, and prepared-execution owner. Prepared handles retain their captured
+// selections whichever related view executes them.
 func (e *Engine) WithNamespaces(namespaces Namespaces) (*Engine, error) {
 	if e == nil || e.internal == nil {
 		return nil, fmt.Errorf("%w: engine is nil", ErrInvalidConfig)