Fix deprecation warnings around class loading during initialization

This:
```
DEPRECATION WARNING: Initialization autoloaded the constant User.

Being able to do this is deprecated. Autoloading during initialization is going
to be an error condition in future versions of Rails.

Reloading does not reboot the application, and therefore code executed during
initialization does not run again. So, if you reload User, for example,
the expected changes won't be reflected in that stale Class object.

This autoloaded constant has been unloaded.

In order to autoload safely at boot time, please wrap your code in a reloader
callback this way:

    Rails.application.reloader.to_prepare do
      # Autoload classes and modules needed at boot time here.
    end

That block runs when the application boots, and every time there is a reload.
For historical reasons, it may run twice, so it has to be idempotent.

Check the "Autoloading and Reloading Constants" guide to learn more about how
Rails autoloads and reloads.
```

config/application.rb

@@ -55,21 +55,27 @@ module Openfoodnetwork
     end
 
     initializer "spree.environment", before: :load_config_initializers do |app|
-      app.config.spree = Spree::Core::Environment.new
-      Spree::Config = app.config.spree.preferences # legacy access
+      Rails.application.reloader.to_prepare do
+        app.config.spree = Spree::Core::Environment.new
+        Spree::Config = app.config.spree.preferences # legacy access
+      end
     end
 
     initializer "spree.register.payment_methods" do |app|
-      app.config.spree.payment_methods = [
-        Spree::Gateway::Bogus,
-        Spree::Gateway::BogusSimple,
-        Spree::PaymentMethod::Check
-      ]
+      Rails.application.reloader.to_prepare do
+        app.config.spree.payment_methods = [
+          Spree::Gateway::Bogus,
+          Spree::Gateway::BogusSimple,
+          Spree::PaymentMethod::Check
+        ]
+      end
     end
 
     initializer "spree.mail.settings" do |_app|
-      Spree::Core::MailSettings.init
-      Mail.register_interceptor(Spree::Core::MailInterceptor)
+      Rails.application.reloader.to_prepare do
+        Spree::Core::MailSettings.init
+        Mail.register_interceptor(Spree::Core::MailInterceptor)
+      end
     end
 
     # filter sensitive information during logging
@@ -93,52 +99,57 @@ module Openfoodnetwork
     # TODO: move back to spree initializer once we upgrade to a more recent version
     #       of Spree
     initializer 'ofn.spree_locale_settings', before: 'spree.promo.environment' do |app|
-      Spree::Config['checkout_zone'] = ENV['CHECKOUT_ZONE']
-      Spree::Config['currency'] = ENV['CURRENCY']
+      Rails.application.reloader.to_prepare do
+        Spree::Config['checkout_zone'] = ENV['CHECKOUT_ZONE']
+        Spree::Config['currency'] = ENV['CURRENCY']
+      end
     end
 
-    # Register Spree calculators
-    Rails.application.reloader.to_prepare do
-      app = Openfoodnetwork::Application
-      app.config.spree.calculators.shipping_methods = [
-        Calculator::FlatPercentItemTotal,
-        Calculator::FlatRate,
-        Calculator::FlexiRate,
-        Calculator::PerItem,
-        Calculator::PriceSack,
-        Calculator::Weight
-      ]
+    initializer "load_spree_calculators" do |app|
+      # Register Spree calculators
+      Rails.application.reloader.to_prepare do
+        app.config.spree.calculators.shipping_methods = [
+          Calculator::FlatPercentItemTotal,
+          Calculator::FlatRate,
+          Calculator::FlexiRate,
+          Calculator::PerItem,
+          Calculator::PriceSack,
+          Calculator::Weight
+        ]
 
-      app.config.spree.calculators.add_class('enterprise_fees')
-      app.config.spree.calculators.enterprise_fees = [
-        Calculator::FlatPercentPerItem,
-        Calculator::FlatRate,
-        Calculator::FlexiRate,
-        Calculator::PerItem,
-        Calculator::PriceSack,
-        Calculator::Weight
-      ]
+        app.config.spree.calculators.add_class('enterprise_fees')
+        app.config.spree.calculators.enterprise_fees = [
+          Calculator::FlatPercentPerItem,
+          Calculator::FlatRate,
+          Calculator::FlexiRate,
+          Calculator::PerItem,
+          Calculator::PriceSack,
+          Calculator::Weight
+        ]
 
-      app.config.spree.calculators.add_class('payment_methods')
-      app.config.spree.calculators.payment_methods = [
-        Calculator::FlatPercentItemTotal,
-        Calculator::FlatRate,
-        Calculator::FlexiRate,
-        Calculator::PerItem,
-        Calculator::PriceSack
-      ]
+        app.config.spree.calculators.add_class('payment_methods')
+        app.config.spree.calculators.payment_methods = [
+          Calculator::FlatPercentItemTotal,
+          Calculator::FlatRate,
+          Calculator::FlexiRate,
+          Calculator::PerItem,
+          Calculator::PriceSack
+        ]
 
-      app.config.spree.calculators.add_class('tax_rates')
-      app.config.spree.calculators.tax_rates = [
-        Calculator::DefaultTax
-      ]
+        app.config.spree.calculators.add_class('tax_rates')
+        app.config.spree.calculators.tax_rates = [
+          Calculator::DefaultTax
+        ]
+      end
     end
 
     # Register Spree payment methods
     initializer "spree.gateway.payment_methods", :after => "spree.register.payment_methods" do |app|
-      app.config.spree.payment_methods << Spree::Gateway::StripeConnect
-      app.config.spree.payment_methods << Spree::Gateway::StripeSCA
-      app.config.spree.payment_methods << Spree::Gateway::PayPalExpress
+      Rails.application.reloader.to_prepare do
+        app.config.spree.payment_methods << Spree::Gateway::StripeConnect
+        app.config.spree.payment_methods << Spree::Gateway::StripeSCA
+        app.config.spree.payment_methods << Spree::Gateway::PayPalExpress
+      end
     end
 
     # Settings in config/environments/* take precedence over those specified here.

config/initializers/content_config.rb

@@ -1 +1,3 @@
-ContentConfig = ContentConfiguration.new
+Rails.application.config.to_prepare do
+  ContentConfig = ContentConfiguration.new
+end

config/initializers/db2fog.rb

@@ -1,15 +1,17 @@
 require_relative 'spree'
 
-# See: https://github.com/itbeaver/db2fog
-DB2Fog.config = {
-    :aws_access_key_id     => Spree::Config[:s3_access_key],
-    :aws_secret_access_key => Spree::Config[:s3_secret],
-    :directory             => ENV['S3_BACKUPS_BUCKET'],
-    :provider              => 'AWS'
-}
+Rails.application.reloader.to_prepare do
+  # See: https://github.com/openfoodfoundation/db2fog
+  DB2Fog.config = {
+      :aws_access_key_id     => Spree::Config[:s3_access_key],
+      :aws_secret_access_key => Spree::Config[:s3_secret],
+      :directory             => ENV['S3_BACKUPS_BUCKET'],
+      :provider              => 'AWS'
+  }
 
-region = ENV['S3_BACKUPS_REGION'] || ENV['S3_REGION']
+  region = ENV['S3_BACKUPS_REGION'] || ENV['S3_REGION']
 
-# If no region is defined we leave this config key undefined (instead of nil),
-# so that db2fog correctly applies it's default
-DB2Fog.config[:region] = region if region
+  # If no region is defined we leave this config key undefined (instead of nil),
+  # so that db2fog correctly applies it's default
+  DB2Fog.config[:region] = region if region
+end

config/initializers/money.rb

@@ -1,2 +1,4 @@
-Money.rounding_mode = BigDecimal::ROUND_HALF_EVEN
-Money.default_currency = Money::Currency.new(ENV.fetch('CURRENCY'))
+Rails.application.reloader.to_prepare do
+  Money.rounding_mode = BigDecimal::ROUND_HALF_EVEN
+  Money.default_currency = Money::Currency.new(ENV.fetch('CURRENCY'))
+end

config/initializers/serializers.rb

@@ -1,2 +1,4 @@
-ActiveModel::ArraySerializer.root = false
-ActiveModel::Serializer.root = false
+Rails.application.reloader.to_prepare do
+  ActiveModel::ArraySerializer.root = false
+  ActiveModel::Serializer.root = false
+end

config/initializers/spree.rb

@@ -8,33 +8,35 @@
 
 require 'spree/core'
 
-Spree.config do |config|
-  config.site_url = ENV['SITE_URL'] if ENV['SITE_URL']
-  config.site_name = ENV['SITE_NAME'] if ENV['SITE_NAME']
-  config.shipping_instructions = true
-  config.address_requires_state = true
-  config.admin_interface_logo = '/default_images/ofn-logo.png'
+Rails.application.reloader.to_prepare do
+  Spree.config do |config|
+    config.site_url = ENV['SITE_URL'] if ENV['SITE_URL']
+    config.site_name = ENV['SITE_NAME'] if ENV['SITE_NAME']
+    config.shipping_instructions = true
+    config.address_requires_state = true
+    config.admin_interface_logo = '/default_images/ofn-logo.png'
 
-  # S3 settings
-  config.s3_bucket = ENV['S3_BUCKET'] if ENV['S3_BUCKET']
-  config.s3_access_key = ENV['S3_ACCESS_KEY'] if ENV['S3_ACCESS_KEY']
-  config.s3_secret = ENV['S3_SECRET'] if ENV['S3_SECRET']
-  config.use_s3 = true if ENV['S3_BUCKET']
-  config.s3_headers = ENV['S3_HEADERS'] if ENV['S3_HEADERS']
-  config.s3_protocol = ENV.fetch('S3_PROTOCOL', 'https')
-end
-
-# Read mail configuration from ENV vars at boot time and ensure the values are
-# applied correctly in Spree::Config.
-MailConfiguration.apply!
-
-# Attachments settings
-Spree::Image.set_attachment_attribute(:path, ENV['ATTACHMENT_PATH']) if ENV['ATTACHMENT_PATH']
-Spree::Image.set_attachment_attribute(:url, ENV['ATTACHMENT_URL']) if ENV['ATTACHMENT_URL']
-Spree::Image.set_storage_attachment_attributes
-
-# TODO Work out why this is necessary
-# Seems like classes within OFN module become 'uninitialized' when server reloads
-# unless the empty module is explicity 'registered' here. Something to do with autoloading?
-module OpenFoodNetwork
+    # S3 settings
+    config.s3_bucket = ENV['S3_BUCKET'] if ENV['S3_BUCKET']
+    config.s3_access_key = ENV['S3_ACCESS_KEY'] if ENV['S3_ACCESS_KEY']
+    config.s3_secret = ENV['S3_SECRET'] if ENV['S3_SECRET']
+    config.use_s3 = true if ENV['S3_BUCKET']
+    config.s3_headers = ENV['S3_HEADERS'] if ENV['S3_HEADERS']
+    config.s3_protocol = ENV.fetch('S3_PROTOCOL', 'https')
+  end
+
+  # Read mail configuration from ENV vars at boot time and ensure the values are
+  # applied correctly in Spree::Config.
+  MailConfiguration.apply!
+
+  # Attachments settings
+  Spree::Image.set_attachment_attribute(:path, ENV['ATTACHMENT_PATH']) if ENV['ATTACHMENT_PATH']
+  Spree::Image.set_attachment_attribute(:url, ENV['ATTACHMENT_URL']) if ENV['ATTACHMENT_URL']
+  Spree::Image.set_storage_attachment_attributes
+
+  # TODO Work out why this is necessary
+  # Seems like classes within OFN module become 'uninitialized' when server reloads
+  # unless the empty module is explicity 'registered' here. Something to do with autoloading?
+  module OpenFoodNetwork
+  end
 end

config/initializers/state_machines.rb

@@ -1,2 +1,4 @@
-# Ignore noisy StateMachines warnings.
-StateMachines::Machine.ignore_method_conflicts = true
+Rails.application.reloader.to_prepare do
+  # Ignore noisy StateMachines warnings.
+  StateMachines::Machine.ignore_method_conflicts = true
+end

config/initializers/storybook.rb

@@ -9,6 +9,7 @@ if Rails.env.development?
     end
   end
 
-  ViewComponent::Storybook::StoriesController.before_action(PermissiveCORSHeaders)
+  Rails.application.reloader.to_prepare do
+    ViewComponent::Storybook::StoriesController.before_action(PermissiveCORSHeaders)
+  end
 end
-

config/initializers/stripe.rb

@@ -10,7 +10,9 @@ module Stripe
   end
 end
 
-Stripe.api_key = ENV['STRIPE_INSTANCE_SECRET_KEY']
-Stripe.publishable_key = ENV['STRIPE_INSTANCE_PUBLISHABLE_KEY']
-Stripe.client_id = ENV['STRIPE_CLIENT_ID']
-Stripe.endpoint_secret = ENV['STRIPE_ENDPOINT_SECRET']
+Rails.application.reloader.to_prepare do
+  Stripe.api_key = ENV['STRIPE_INSTANCE_SECRET_KEY']
+  Stripe.publishable_key = ENV['STRIPE_INSTANCE_PUBLISHABLE_KEY']
+  Stripe.client_id = ENV['STRIPE_CLIENT_ID']
+  Stripe.endpoint_secret = ENV['STRIPE_ENDPOINT_SECRET']
+end

config/initializers/wicked_pdf.rb

@@ -1,8 +1,10 @@
-WickedPdf.config = {
-  #:wkhtmltopdf => '/usr/local/bin/wkhtmltopdf',
-  #:layout => "pdf.html",
-  :exe_path => `bundle exec which wkhtmltopdf`.chomp
-}
+Rails.application.reloader.to_prepare do
+  WickedPdf.config = {
+    #:wkhtmltopdf => '/usr/local/bin/wkhtmltopdf',
+    #:layout => "pdf.html",
+    :exe_path => `bundle exec which wkhtmltopdf`.chomp
+  }
+end
 
 # A monkey-patch to remove WickedPdf's monkey-patch, as it clashes with ViewComponents.
 class WickedPdf