feature: support open router

Author: densumesh

src/v1/resources/chat.rs

@@ -232,8 +232,6 @@ pub struct DeltaFunction {
 
 #[derive(Serialize, Deserialize, Debug, Clone, PartialEq)]
 pub struct ChatCompletionChoice {
-    /// The index of the choice in the list of choices.
-    pub index: u32,
     /// A chat completion message generated by the model.
     pub message: ChatMessage,
     /// The reason the model stopped generating tokens.
@@ -243,8 +241,6 @@ pub struct ChatCompletionChoice {
 #[cfg(feature = "stream")]
 #[derive(Serialize, Deserialize, Debug, Clone, PartialEq)]
 pub struct ChatCompletionChunkChoice {
-    /// The index of the choice in the list of choices.
-    pub index: u32,
     /// A chat completion delta generated by streamed model responses.
     pub delta: DeltaChatMessage,
     /// The reason the model stopped generating tokens.