add migrations for dietary restrictions

separating out the migrations for dietary restrictions so we can apply
these to production before deploying the code that makes use of the new
columns.

Author: mikej

db/migrate/20250820134727_create_dietary_restriction_enum.rb

@@ -0,0 +1,5 @@
+class CreateDietaryRestrictionEnum < ActiveRecord::Migration[7.1]
+  def change
+    create_enum :dietary_restriction_enum, %w[vegan vegetarian pescetarian halal gluten_free dairy_free other]
+  end
+end

db/migrate/20250820145012_add_dietary_restrictions_to_members.rb

@@ -0,0 +1,6 @@
+class AddDietaryRestrictionsToMembers < ActiveRecord::Migration[7.0]
+  def change
+    add_column :members, :dietary_restrictions, :enum, enum_type: "dietary_restriction_enum", array: true, default: []
+    add_column :members, :other_dietary_restrictions, :string
+  end
+end