[feature] [sgl-router] Add a dp-aware routing strategy (#6869)

sgl-router/src/core/error.rs

@@ -17,6 +17,8 @@ pub enum WorkerError {
     NetworkError { url: String, error: String },
     /// Worker is at capacity
     WorkerAtCapacity { url: String },
+    /// Invalid URL format
+    InvalidUrl { url: String },
 }
 
 impl fmt::Display for WorkerError {
@@ -37,6 +39,9 @@ impl fmt::Display for WorkerError {
             WorkerError::WorkerAtCapacity { url } => {
                 write!(f, "Worker at capacity: {}", url)
             }
+            WorkerError::InvalidUrl { url } => {
+                write!(f, "Invalid URL format: {}", url)
+            }
         }
     }
 }