Marketplace: sync projects into their containers on start

Waits for the entrypoint, uploads the payload and the sync script, runs it
as claude and stores its report (payload skips merged in). The start hook
spawns the sync in the background; a per-project lock serialises syncs of
one project (pre-flight F11b).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

app/src-tauri/src/commands/project_commands.rs

@@ -1449,6 +1449,16 @@ async fn start_project_container_locked(
             log::warn!("Failed to sync AWS credentials for project {}: {}", project.id, e);
         }
 
+        // Marketplace items sync in the background — see `spawn_project_sync`
+        // for why the start never waits on it or fails because of it.
+        crate::marketplace::spawn_project_sync(
+            app_handle.clone(),
+            state.marketplace.clone(),
+            state.settings_store.get(),
+            project.clone(),
+            container_id.clone(),
+        );
+
         Ok(container_id)
     }.await;