feat(users): new routes to accept invite and list merchants (#4591)

crates/router_env/src/logger/types.rs

@@ -386,6 +386,8 @@ pub enum Flow {
     UpdateUserAccountDetails,
     /// Accept user invitation
     AcceptInvitation,
+    /// Select merchant from invitations
+    MerchantSelect,
     /// Initiate external authentication for a payment
     PaymentsExternalAuthentication,
     /// Authorize the payment after external 3ds authentication