Use shared inbox when available

But it is not yet stored in the database, so it means never

src/models/blogs.rs

@@ -15,7 +15,7 @@ use models::instance::Instance;
 use schema::blogs;
 
 
-#[derive(Queryable, Identifiable, Serialize)]
+#[derive(Queryable, Identifiable, Serialize, Clone)]
 pub struct Blog {
     pub id: i32,
     pub actor_id: String,
@@ -130,6 +130,10 @@ impl Actor for Blog {
         self.inbox_url.clone()
     }
 
+    fn get_shared_inbox_url(&self) -> Option<String> {
+        None
+    }
+
     fn from_url(conn: &PgConnection, url: String) -> Option<Blog> {
         blogs::table.filter(blogs::ap_url.eq(url))
             .limit(1)

src/models/users.rs

@@ -300,6 +300,10 @@ impl Actor for User {
         self.inbox_url.clone()
     }
 
+    fn get_shared_inbox_url(&self) -> Option<String> {
+       None
+    }
+
     fn custom_props(&self, conn: &PgConnection) -> serde_json::Map<String, serde_json::Value> {
         let mut res = serde_json::Map::new();
         res.insert("publicKey".to_string(), json!({