feat: Add optional serde support for RithmicEnv

Add serde feature flag that enables Serialize/Deserialize derives
for RithmicEnv. Also adds Copy and Default traits to the enum.

Author: pbeets

Cargo.toml

@@ -12,7 +12,12 @@ categories = ["api-bindings", "finance"]
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
+[features]
+default = []
+serde = ["dep:serde"]
+
 [dependencies]
+serde = { version = "1", features = ["derive"], optional = true }
 async-trait = "0.1.88"
 futures-util = "0.3.31"
 prost = "0.13.5"

src/config.rs

@@ -26,8 +26,11 @@ use std::{env, fmt, str::FromStr};
 /// Trading environment selector.
 ///
 /// Determines which Rithmic environment to connect to.
-#[derive(Clone, Debug, PartialEq, Eq)]
+#[derive(Clone, Copy, Debug, Default, PartialEq, Eq)]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
+#[cfg_attr(feature = "serde", serde(rename_all = "lowercase"))]
 pub enum RithmicEnv {
+    #[default]
     Demo,
     Live,
     Test,