fix(membership-fees): add DB constraints for enum and decimal precision

lib/membership_fees/membership_fee_cycle.ex

@@ -65,7 +65,9 @@ defmodule Mv.MembershipFees.MembershipFeeCycle do
     attribute :amount, :decimal do
       allow_nil? false
       public? true
+
       description "Fee amount for this cycle (stored for audit trail, non-negative, max 2 decimal places)"
+
       constraints min: 0, scale: 2
     end
 

priv/repo/migrations/20251211151449_add_membership_fees_tables.exs

@@ -133,6 +133,7 @@ defmodule Mv.Repo.Migrations.AddMembershipFeesTables do
     drop_if_exists unique_index(:membership_fee_types, [:name],
                      name: "membership_fee_types_unique_name_index"
                    )
+
     drop_if_exists constraint(:membership_fee_types, :membership_fee_types_interval_check)
     drop_if_exists constraint(:membership_fee_types, :membership_fee_types_amount_check)