feat: event store — persist domain events to Postgres event_log table via composite publisher

crates/adapters/event-transport/src/composite.rs

@@ -0,0 +1,26 @@
+use async_trait::async_trait;
+use domain::{
+    errors::DomainError,
+    events::DomainEvent,
+    ports::{EventPublisher, EventStore},
+};
+use std::sync::Arc;
+
+pub struct CompositeEventPublisher {
+    primary: Arc<dyn EventPublisher>,
+    store: Arc<dyn EventStore>,
+}
+
+impl CompositeEventPublisher {
+    pub fn new(primary: Arc<dyn EventPublisher>, store: Arc<dyn EventStore>) -> Self {
+        Self { primary, store }
+    }
+}
+
+#[async_trait]
+impl EventPublisher for CompositeEventPublisher {
+    async fn publish(&self, event: &DomainEvent) -> Result<(), DomainError> {
+        self.store.append(event).await?;
+        self.primary.publish(event).await
+    }
+}

crates/adapters/event-transport/src/lib.rs

@@ -1,3 +1,6 @@
+pub mod composite;
+pub use composite::CompositeEventPublisher;
+
 use async_trait::async_trait;
 use domain::{
     errors::DomainError,