refactor: apply zero-unwrap policy and optimize locks in store.rs and handlers

mcp-stdio/src/lib.rs

@@ -21,21 +21,21 @@ pub async fn read_mcp_message<R: tokio::io::AsyncRead + Unpin>(
         if line.is_empty() {
             break;
         }
-        
+
         let lower_line = line.to_lowercase();
         if let Some(len_str) = lower_line.strip_prefix("content-length:") {
             length = len_str.trim().parse().unwrap_or(0);
         }
     }
-    
+
     if length == 0 {
         return None;
     }
-    
+
     let mut buffer = vec![0; length];
     if stdin.read_exact(&mut buffer).await.is_err() {
         return None;
     }
-    
+
     String::from_utf8(buffer).ok()
 }