chore: extract arbitrary into its own crate arbitrary-value

arbitrary-value/src/map.rs

@@ -0,0 +1,7 @@
+use std::collections::BTreeMap;
+
+use super::{arbitrary::Arbitrary, map_key::MapKey};
+
+#[cfg_attr(feature = "pyo3", derive(pyo3::FromPyObject, pyo3::IntoPyObject))]
+#[derive(Debug, Clone, Default, derive_more::From, derive_more::Into)]
+pub struct Map(pub BTreeMap<MapKey, Arbitrary>);