fix: remove unused one_f64 function and fix test compilation

- Remove unused one_f64() function that was causing CI warnings
- Remove unused serde default attribute from Provider.weight field
- Add missing weighted_rpc_steering field to test fixtures
- Apply cargo fmt formatting fixes

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude

Author: DaMandal0rian

node/src/chain.rs

@@ -427,6 +427,7 @@ mod test {
             ethereum_ws: vec![],
             ethereum_ipc: vec![],
             unsafe_config: false,
+            weighted_rpc_steering: false,
         };
 
         let metrics = Arc::new(EndpointMetrics::mock());

node/src/config.rs

@@ -563,7 +563,7 @@ impl Chain {
         if labels.len() != self.providers.len() {
             return Err(anyhow!("Provider labels must be unique"));
         }
-        
+
         // Check that not all provider weights are zero
         if !self.providers.is_empty() {
             let all_zero_weights = self.providers.iter().all(|p| p.weight == 0.0);
@@ -608,7 +608,6 @@ fn btree_map_to_http_headers(kvs: BTreeMap<String, String>) -> HeaderMap {
 pub struct Provider {
     pub label: String,
     pub details: ProviderDetails,
-    #[serde(default = "one_f64")]
     pub weight: f64,
 }
 
@@ -1174,10 +1173,6 @@ fn one() -> usize {
     1
 }
 
-fn one_f64() -> f64 {
-    1.0
-}
-
 fn default_node_id() -> NodeId {
     NodeId::new("default").unwrap()
 }