Billing (#1269)

* Change env SELF_HOSTING_ENABLED to SELF_HOSTED

* Initial Stripe implementation

* Fix portal link

* Use webhook signatures

* Migrated to new Stripe gem conventions

Also updated resource routing

* Added faraday-multipart gem to resolve middleware notice

* Merge fix

* Merge fix

* Temporary upgrade prompt for early access

* Lint fix

* i18n fixes

* Remove catch-all rescue

* Update .env.example

db/migrate/20241007211438_add_billing_to_families.rb

@@ -0,0 +1,7 @@
+class AddBillingToFamilies < ActiveRecord::Migration[7.2]
+  def change
+    add_column :families, :stripe_plan_id, :string
+    add_column :families, :stripe_customer_id, :string
+    add_column :families, :stripe_subscription_status, :string, default: "incomplete"
+  end
+end