fix: truncate remote actor username to VARCHAR(32); fix outbox URL by following 'first' link

crates/adapters/activitypub-base/src/service.rs

@@ -1528,8 +1528,26 @@ impl domain::ports::FederationActionPort for ActivityPubService {
     ) -> Result<Vec<domain::models::remote_note::RemoteNote>, domain::errors::DomainError> {
         use chrono::DateTime;
 
-        let url = format!("{}?page={}", outbox_url, page);
-        let resp: serde_json::Value = reqwest::Client::new()
+        // Fetch the base outbox to find the real first-page URL.
+        // Mastodon uses ?page=true; other servers may use ?page=1 or a different param.
+        let client = reqwest::Client::new();
+        let base: serde_json::Value = client
+            .get(outbox_url)
+            .header("Accept", "application/activity+json, application/ld+json")
+            .send()
+            .await
+            .map_err(|e| domain::errors::DomainError::ExternalService(e.to_string()))?
+            .json()
+            .await
+            .map_err(|e| domain::errors::DomainError::ExternalService(e.to_string()))?;
+
+        // Prefer the `first` link from the OrderedCollection; fall back to ?page=1.
+        let url = base["first"]
+            .as_str()
+            .map(|s| s.to_string())
+            .unwrap_or_else(|| format!("{}?page={}", outbox_url, page));
+
+        let resp: serde_json::Value = client
             .get(&url)
             .header("Accept", "application/activity+json, application/ld+json")
             .send()