xml: Implement proper NamespaceOwned type

crates/xml/src/namespace.rs

@@ -0,0 +1,34 @@
+use quick_xml::name::Namespace;
+
+#[derive(Debug, Clone, Default, PartialEq)]
+pub struct NamespaceOwned(pub Vec<u8>);
+
+impl<'a> From<Namespace<'a>> for NamespaceOwned {
+    fn from(value: Namespace<'a>) -> Self {
+        Self(value.0.to_vec())
+    }
+}
+
+impl From<String> for NamespaceOwned {
+    fn from(value: String) -> Self {
+        Self(value.into_bytes())
+    }
+}
+
+impl From<&str> for NamespaceOwned {
+    fn from(value: &str) -> Self {
+        Self(value.as_bytes().to_vec())
+    }
+}
+
+impl<'a> From<&'a Namespace<'a>> for NamespaceOwned {
+    fn from(value: &'a Namespace<'a>) -> Self {
+        Self(value.0.to_vec())
+    }
+}
+
+impl NamespaceOwned {
+    pub fn as_ref(&self) -> Namespace {
+        Namespace(&self.0)
+    }
+}