fix: wire DeliveryRequested federation events — outbound AP delivery was broken

FederationEventBridge silently dropped DeliveryRequested events from k-ap,
so no Create/Delete/Accept activities were pushed to follower inboxes.
Reviews only reached remote instances via outbox backfill (pull), and
deletes never propagated.

Bridge now publishes FederationDeliveryRequested domain events through the
event bus; worker calls ap_service.deliver_to_inbox() to send them.

crates/adapters/activitypub/src/event_handler.rs

@@ -80,6 +80,23 @@ impl EventHandler for ActivityPubEventHandler {
                 .on_watchlist_removed(user_id, movie_id)
                 .await
                 .map_err(|e| DomainError::InfrastructureError(e.to_string())),
+            DomainEvent::FederationDeliveryRequested {
+                inbox_url,
+                activity_json,
+                signing_actor_id,
+            } => {
+                let inbox: url::Url = inbox_url
+                    .parse()
+                    .map_err(|e| DomainError::InfrastructureError(format!("bad inbox URL: {e}")))?;
+                let activity: serde_json::Value =
+                    serde_json::from_str(activity_json).map_err(|e| {
+                        DomainError::InfrastructureError(format!("bad activity JSON: {e}"))
+                    })?;
+                self.ap_service
+                    .deliver_to_inbox(inbox, activity, *signing_actor_id)
+                    .await
+                    .map_err(|e| DomainError::InfrastructureError(e.to_string()))
+            }
             _ => Ok(()),
         }
     }

crates/adapters/activitypub/src/federation_event_bridge.rs

@@ -29,8 +29,24 @@ impl k_ap::EventPublisher for FederationEventBridge {
                 })
                 .await
                 .map_err(|e| anyhow::anyhow!(e.to_string())),
-            _ => {
-                tracing::debug!("ignoring federation event: {:?}", event);
+            FederationEvent::DeliveryRequested {
+                inbox,
+                activity,
+                signing_actor_id,
+            } => {
+                let json = serde_json::to_string(&activity)
+                    .map_err(|e| anyhow::anyhow!("serialize activity: {e}"))?;
+                self.domain_publisher
+                    .publish(&DomainEvent::FederationDeliveryRequested {
+                        inbox_url: inbox.to_string(),
+                        activity_json: json,
+                        signing_actor_id,
+                    })
+                    .await
+                    .map_err(|e| anyhow::anyhow!(e.to_string()))
+            }
+            other => {
+                tracing::debug!("ignoring federation event: {:?}", other);
                 Ok(())
             }
         }

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

@@ -67,6 +67,11 @@ pub enum EventPayload {
         owner_user_id: String,
         follower_inbox_url: String,
     },
+    FederationDeliveryRequested {
+        inbox_url: String,
+        activity_json: String,
+        signing_actor_id: String,
+    },
 }
 
 impl EventPayload {
@@ -84,6 +89,7 @@ impl EventPayload {
             EventPayload::WatchlistEntryRemoved { .. } => "WatchlistEntryRemoved",
             EventPayload::FollowAccepted { .. } => "FollowAccepted",
             EventPayload::BackfillFollower { .. } => "BackfillFollower",
+            EventPayload::FederationDeliveryRequested { .. } => "FederationDeliveryRequested",
         }
     }
 }
@@ -193,6 +199,15 @@ impl From<&DomainEvent> for EventPayload {
                 owner_user_id: owner_user_id.value().to_string(),
                 follower_inbox_url: follower_inbox_url.clone(),
             },
+            DomainEvent::FederationDeliveryRequested {
+                inbox_url,
+                activity_json,
+                signing_actor_id,
+            } => EventPayload::FederationDeliveryRequested {
+                inbox_url: inbox_url.clone(),
+                activity_json: activity_json.clone(),
+                signing_actor_id: signing_actor_id.to_string(),
+            },
         }
     }
 }
@@ -300,6 +315,15 @@ impl TryFrom<EventPayload> for DomainEvent {
                 owner_user_id: UserId::from_uuid(parse_uuid(&owner_user_id, "owner_user_id")?),
                 follower_inbox_url,
             }),
+            EventPayload::FederationDeliveryRequested {
+                inbox_url,
+                activity_json,
+                signing_actor_id,
+            } => Ok(DomainEvent::FederationDeliveryRequested {
+                inbox_url,
+                activity_json,
+                signing_actor_id: parse_uuid(&signing_actor_id, "signing_actor_id")?,
+            }),
         }
     }
 }

crates/adapters/nats/src/subject.rs

@@ -14,6 +14,7 @@ pub fn event_to_subject(prefix: &str, event: &DomainEvent) -> String {
         DomainEvent::WatchlistEntryRemoved { .. } => "watchlist.entry.removed",
         DomainEvent::FollowAccepted { .. } => "follow.accepted",
         DomainEvent::BackfillFollower { .. } => "backfill.follower",
+        DomainEvent::FederationDeliveryRequested { .. } => "federation.delivery.requested",
     };
     format!("{prefix}.{suffix}")
 }

crates/application/src/tests/worker.rs

@@ -57,6 +57,7 @@ impl EventHandler for RecordingHandler {
             }
             DomainEvent::FollowAccepted { .. } => "follow_accepted",
             DomainEvent::BackfillFollower { .. } => "backfill_follower",
+            DomainEvent::FederationDeliveryRequested { .. } => "federation_delivery",
         };
         self.calls.lock().unwrap().push(label);
         Ok(())

crates/domain/src/events.rs

@@ -65,6 +65,11 @@ pub enum DomainEvent {
         owner_user_id: UserId,
         follower_inbox_url: String,
     },
+    FederationDeliveryRequested {
+        inbox_url: String,
+        activity_json: String,
+        signing_actor_id: uuid::Uuid,
+    },
 }
 
 #[async_trait]