Add macro to get rustc version. (#62)

Add macro to query git-describe. (#62)

Signed-off-by: Jason Volk <jason@zemos.net>

src/core/info/version.rs

@@ -9,6 +9,7 @@ use std::sync::OnceLock;
 
 static BRANDING: &str = "Tuwunel";
 static SEMANTIC: &str = env!("CARGO_PKG_VERSION");
+tuwunel_macros::git_describe!();
 
 static VERSION: OnceLock<String> = OnceLock::new();
 static USER_AGENT: OnceLock<String> = OnceLock::new();