Bump namespace to 04
diff --git a/macro/src/expand.rs b/macro/src/expand.rs
index c2d88ce..2f797b0 100644
--- a/macro/src/expand.rs
+++ b/macro/src/expand.rs
@@ -689,7 +689,7 @@
 }
 
 fn expand_rust_box(namespace: &Namespace, ident: &Ident) -> TokenStream {
-    let link_prefix = format!("cxxbridge03$box${}{}$", namespace, ident);
+    let link_prefix = format!("cxxbridge04$box${}{}$", namespace, ident);
     let link_uninit = format!("{}uninit", link_prefix);
     let link_drop = format!("{}drop", link_prefix);
 
@@ -718,7 +718,7 @@
 }
 
 fn expand_rust_vec(namespace: &Namespace, elem: &Ident) -> TokenStream {
-    let link_prefix = format!("cxxbridge03$rust_vec${}{}$", namespace, elem);
+    let link_prefix = format!("cxxbridge04$rust_vec${}{}$", namespace, elem);
     let link_new = format!("{}new", link_prefix);
     let link_drop = format!("{}drop", link_prefix);
     let link_len = format!("{}len", link_prefix);
@@ -764,7 +764,7 @@
 
 fn expand_unique_ptr(namespace: &Namespace, ident: &Ident, types: &Types) -> TokenStream {
     let name = ident.to_string();
-    let prefix = format!("cxxbridge03$unique_ptr${}{}$", namespace, ident);
+    let prefix = format!("cxxbridge04$unique_ptr${}{}$", namespace, ident);
     let link_null = format!("{}null", prefix);
     let link_new = format!("{}new", prefix);
     let link_raw = format!("{}raw", prefix);
@@ -837,10 +837,10 @@
 
 fn expand_cxx_vector(namespace: &Namespace, elem: &Ident) -> TokenStream {
     let name = elem.to_string();
-    let prefix = format!("cxxbridge03$std$vector${}{}$", namespace, elem);
+    let prefix = format!("cxxbridge04$std$vector${}{}$", namespace, elem);
     let link_size = format!("{}size", prefix);
     let link_get_unchecked = format!("{}get_unchecked", prefix);
-    let unique_ptr_prefix = format!("cxxbridge03$unique_ptr$std$vector${}{}$", namespace, elem);
+    let unique_ptr_prefix = format!("cxxbridge04$unique_ptr$std$vector${}{}$", namespace, elem);
     let link_unique_ptr_null = format!("{}null", unique_ptr_prefix);
     let link_unique_ptr_raw = format!("{}raw", unique_ptr_prefix);
     let link_unique_ptr_get = format!("{}get", unique_ptr_prefix);