New onboarding, trials, Stripe integration (#2185)

* New onboarding, trials, Stripe integration

* Fix tests

* Lint fixes

* Fix subscription endpoints

app/models/provider/stripe/subscription_event_processor.rb

@@ -0,0 +1,29 @@
+class Provider::Stripe::SubscriptionEventProcessor < Provider::Stripe::EventProcessor
+  Error = Class.new(StandardError)
+
+  def process
+    raise Error, "Family not found for Stripe customer ID: #{customer_id}" unless family
+
+    family.update(
+      stripe_plan_id: plan_id,
+      stripe_subscription_status: subscription_status
+    )
+  end
+
+  private
+    def family
+      Family.find_by(stripe_customer_id: customer_id)
+    end
+
+    def customer_id
+      event_data.customer
+    end
+
+    def plan_id
+      event_data.plan.id
+    end
+
+    def subscription_status
+      event_data.status
+    end
+end