Release v0.4.0

Changed

• Strict read-model scenarios (ReadModelOptions.StrictEventSubscription) now decide whether a seeded event is subscribed the same way the kernel does for the projection. Children, joins, nested scopes, removal events and derived event types all count, and keys do not. Strict scenarios no longer refuse relationship, custom-key or mixed-All projections when they open. Unsubscribed seeds are still rejected in Given with ErrUnsubscribedEventSeeded before anything is appended. Reading results for those profiles still returns ErrUnsupported (part of #38)

Fixed

• A strict scenario now rejects a root-level join-removal event as unsubscribed, matching the kernel, instead of refusing the whole projection (part of #38)