chore: add dead code allowance for delete_blob function

src/model/msglog/blobs.rs

@@ -23,6 +23,7 @@ pub fn retrieve_blob(conn: &Connection, session_id: &str, blob_key: &str) -> Res
     }
 }
 
+#[allow(dead_code)]
 pub fn delete_blob(conn: &Connection, session_id: &str, blob_key: &str) -> Result<bool> {
     let rows = conn.execute(
         "DELETE FROM blobs WHERE session_id = ?1 AND blob_key = ?2",