feat: add ToSnakeCaseString derive macro support

Co-authored-by: aider (openai/andrew/openrouter/deepseek/deepseek-chat-v3.1) <aider@aider.chat>

src/lib.rs

@@ -14,5 +14,8 @@ pub use args::Args;
 // Re-export PIPESIZE constant
 pub use common::PIPESIZE;
 
+// Re-export the ToSnakeCaseString trait and derive macro
+pub use to_snake_case_string::ToSnakeCaseString;
+
 #[cfg(test)]
 mod tests;