feat(framework): Added diff-checker required code and running ucs in shadow mode (#9684)

Co-authored-by: hyperswitch-bot[bot] <148525504+hyperswitch-bot[bot]@users.noreply.github.com>

crates/common_enums/src/enums.rs

@@ -2274,6 +2274,33 @@ pub enum GatewaySystem {
     #[default]
     Direct,
     UnifiedConnectorService,
+    ShadowUnifiedConnectorService,
+}
+
+#[derive(
+    Clone,
+    Copy,
+    Debug,
+    Default,
+    Eq,
+    PartialOrd,
+    Ord,
+    Hash,
+    PartialEq,
+    serde::Deserialize,
+    serde::Serialize,
+    strum::Display,
+    strum::VariantNames,
+    strum::EnumIter,
+    strum::EnumString,
+    ToSchema,
+)]
+#[serde(rename_all = "snake_case")]
+#[strum(serialize_all = "snake_case")]
+pub enum ExecutionMode {
+    #[default]
+    Primary,
+    Shadow,
 }
 
 /// The type of the payment that differentiates between normal and various types of mandate payments. Use 'setup_mandate' in case of zero auth flow.