fix: persist inbound Block to blocklist, clear on Undo(Block)

Closes #1

src/activities/block.rs

@@ -46,17 +46,22 @@ impl Activity for BlockActivity {
         if check_guards(&self.id, self.actor.inner(), data).await? {
             return Ok(());
         }
+        let actor_url = self.actor.inner().as_str();
         if let Some(local_user_id) = crate::urls::extract_user_id_from_url(&self.object) {
             let _ = data
                 .follow_repo
-                .remove_following(local_user_id, self.actor.inner().as_str())
+                .remove_following(local_user_id, actor_url)
                 .await;
             let _ = data
                 .follow_repo
-                .remove_follower(local_user_id, self.actor.inner().as_str())
+                .remove_follower(local_user_id, actor_url)
+                .await;
+            let _ = data
+                .blocklist_repo
+                .add_blocked_actor(local_user_id, actor_url)
                 .await;
         }
-        tracing::info!(actor = %self.actor.inner(), "received block — removed following and follower");
+        tracing::info!(actor = %actor_url, "received block — removed relationships, recorded in blocklist");
         Ok(())
     }
 }

src/activities/undo.rs

@@ -128,11 +128,18 @@ impl Activity for UndoActivity {
                 tracing::info!(actor = %self.actor.inner(), "received Undo(Announce)");
             }
             "Block" => {
-                // Remote actor unblocked a local user. No automatic relationship
-                // restoration — the blocked user would need to re-follow manually.
+                if let Some(obj_url) = self.object.get("object").and_then(|o| o.as_str())
+                    && let Ok(url) = Url::parse(obj_url)
+                    && let Some(user_id) = crate::urls::extract_user_id_from_url(&url)
+                {
+                    let _ = data
+                        .blocklist_repo
+                        .remove_blocked_actor(user_id, self.actor.inner().as_str())
+                        .await;
+                }
                 tracing::info!(
                     actor = %self.actor.inner(),
-                    "received Undo(Block) — no automatic action taken"
+                    "received Undo(Block) — removed from blocklist"
                 );
             }
             other => {