fix(events): register WriteScopeGrantedEvent in eventModule (#301 silent-deser trap)

The #301 escalation event shipped unregistered — it would silently fail to
deserialize on replay, dropping the persisted write-scope grant and re-prompting
the same path every session restart (breaks replay invariant).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

core/events/src/main/kotlin/com/correx/core/events/serialization/Serialization.kt

@@ -71,6 +71,7 @@ import com.correx.core.events.events.BuildPrerequisiteBootstrapAttemptedEvent
 import com.correx.core.events.events.WorkspaceVerificationObservedEvent
 import com.correx.core.events.events.PlanGroundingEvaluatedEvent
 import com.correx.core.events.events.OutsidePathAccessGrantedEvent
+import com.correx.core.events.events.WriteScopeGrantedEvent
 import com.correx.core.events.events.WorkspaceStateObservedEvent
 import com.correx.core.events.events.RiskAssessedEvent
 import com.correx.core.events.events.SourceFetchedEvent
@@ -168,6 +169,7 @@ val eventModule = SerializersModule {
         subclass(WorkspaceVerificationObservedEvent::class)
         subclass(PlanGroundingEvaluatedEvent::class)
         subclass(OutsidePathAccessGrantedEvent::class)
+        subclass(WriteScopeGrantedEvent::class)
         subclass(RefinementIterationEvent::class)
         subclass(RepoMapComputedEvent::class)
         subclass(WorkspaceStateObservedEvent::class)