feat(storage_impl): split payment intent interface implementation (#1946)

crates/data_models/src/lib.rs

@@ -0,0 +1,25 @@
+pub mod errors;
+pub mod mandates;
+pub mod payments;
+
+// TODO: This decision about using KV mode or not,
+// should be taken at a top level rather than pushing it down to individual functions via an enum.
+#[derive(
+    Clone,
+    Copy,
+    Debug,
+    Default,
+    Eq,
+    PartialEq,
+    serde::Deserialize,
+    serde::Serialize,
+    strum::Display,
+    strum::EnumString,
+)]
+#[serde(rename_all = "snake_case")]
+#[strum(serialize_all = "snake_case")]
+pub enum MerchantStorageScheme {
+    #[default]
+    PostgresOnly,
+    RedisKv,
+}