feat(derive): Add derive macro for interface

crates/char_sdk_derive/Cargo.toml

@@ -0,0 +1,12 @@
+[package]
+name = "char_sdk_derive"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+syn = "1.0.107"
+quote = "1.0.23"
+[lib]
+proc-macro = true

crates/char_sdk_derive/src/lib.rs

@@ -0,0 +1,24 @@
+extern crate proc_macro;
+
+use proc_macro::TokenStream;
+use quote::quote;
+
+#[proc_macro_derive(CharAction)]
+pub fn derive_char_action_into_box(input: TokenStream) -> TokenStream {
+    let ast = syn::parse(input).unwrap();
+
+    // Build the trait implementation
+    impl_hello_macro(&ast)
+}
+
+fn impl_hello_macro(ast: &syn::DeriveInput) -> TokenStream {
+    let name = &ast.ident;
+    let gen = quote! {
+        impl Into<Box<dyn char_sdk::Action>> for #name {
+            fn into(self) -> Box<dyn char_sdk::Action> {
+                Box::new(self)
+            }
+        }
+    };
+    gen.into()
+}