Reuse OpenAI low_speed_timeout setting for zed.dev provider (#18144)

Release Notes:

- N/A

crates/language_model/src/settings.rs

@@ -231,6 +231,7 @@ pub struct GoogleSettingsContent {
 #[derive(Default, Clone, Debug, Serialize, Deserialize, PartialEq, JsonSchema)]
 pub struct ZedDotDevSettingsContent {
     available_models: Option<Vec<cloud::AvailableModel>>,
+    pub low_speed_timeout_in_seconds: Option<u64>,
 }
 
 #[derive(Default, Clone, Debug, Serialize, Deserialize, PartialEq, JsonSchema)]
@@ -333,6 +334,14 @@ impl settings::Settings for AllLanguageModelSettings {
                     .as_ref()
                     .and_then(|s| s.available_models.clone()),
             );
+            if let Some(low_speed_timeout_in_seconds) = value
+                .zed_dot_dev
+                .as_ref()
+                .and_then(|s| s.low_speed_timeout_in_seconds)
+            {
+                settings.zed_dot_dev.low_speed_timeout =
+                    Some(Duration::from_secs(low_speed_timeout_in_seconds));
+            }
 
             merge(
                 &mut settings.google.api_url,