refactor: apply 5-pass audit optimizations across mcp-memory codebase

server/src/lib.rs

@@ -122,10 +122,8 @@ pub async fn ttl_sweeper_worker(state: Arc<MemoryState>) {
 pub async fn index_committer_worker(state: Arc<MemoryState>) {
     loop {
         state.index_commit_notify.notified().await;
-        let idx_opt = state.search_index.read().ok().map(|idx| idx.clone());
-        if let Some(idx) = idx_opt {
-            let _ = idx.commit().await;
-        }
+        let idx = state.search_index.read().await.clone();
+        let _ = idx.commit().await;
     }
 }
 
@@ -234,15 +232,26 @@ pub async fn run_server(state: Arc<MemoryState>) -> Result<(), Box<dyn std::erro
         loop {
             match rx.recv().await {
                 Ok(msg) => {
-                    let senders: Vec<_> = app_state_clone
-                        .clients
-                        .read()
-                        .unwrap_or_else(|e| e.into_inner())
-                        .values()
-                        .cloned()
-                        .collect();
-                    for client_tx in senders {
-                        let _ = client_tx.try_send(msg.clone());
+                    let mut closed_ids = Vec::new();
+                    {
+                        let clients_guard = app_state_clone
+                            .clients
+                            .read()
+                            .unwrap_or_else(|e| e.into_inner());
+                        for (id, tx) in clients_guard.iter() {
+                            if tx.try_send(msg.clone()).is_err() && tx.is_closed() {
+                                closed_ids.push(id.clone());
+                            }
+                        }
+                    }
+                    if !closed_ids.is_empty() {
+                        let mut write_guard = app_state_clone
+                            .clients
+                            .write()
+                            .unwrap_or_else(|e| e.into_inner());
+                        for id in closed_ids {
+                            write_guard.remove(&id);
+                        }
                     }
                 }
                 Err(tokio::sync::broadcast::error::RecvError::Closed) => break,
@@ -304,9 +313,14 @@ pub async fn run_server(state: Arc<MemoryState>) -> Result<(), Box<dyn std::erro
                         let session = &payload.session_id;
                         let _is_unix_socket = session.starts_with('/') || session.starts_with('~');
                         if let Some(home) = dirs::home_dir() {
-                            let nvim_txt_path = home.join(".gemini").join("active_nvim.txt");
-                            let _ = tokio::fs::create_dir_all(nvim_txt_path.parent().unwrap()).await;
-                            let _ = tokio::fs::write(&nvim_txt_path, session).await;
+                            let nvim_dir = home.join(".gemini");
+                            let nvim_txt_path = nvim_dir.join("active_nvim.txt");
+                            let tmp_path = nvim_dir.join(format!("active_nvim_{}.tmp", std::process::id()));
+                            if tokio::fs::create_dir_all(&nvim_dir).await.is_ok()
+                                && tokio::fs::write(&tmp_path, session).await.is_ok()
+                            {
+                                let _ = tokio::fs::rename(&tmp_path, &nvim_txt_path).await;
+                            }
                         }
                     }