collab: Record cancellation reason on billing subscriptions (#22853)

This PR updates the `billing_subscriptions` in the database to record
the cancellation reason from Stripe.

We're primarily interested in this so we can check for subscriptions
that were canceled for being `past_due`.

Release Notes:

- N/A

crates/collab/src/db/queries/billing_subscriptions.rs

@@ -1,4 +1,4 @@
-use crate::db::billing_subscription::StripeSubscriptionStatus;
+use crate::db::billing_subscription::{StripeCancellationReason, StripeSubscriptionStatus};
 
 use super::*;
 
@@ -15,6 +15,7 @@ pub struct UpdateBillingSubscriptionParams {
     pub stripe_subscription_id: ActiveValue<String>,
     pub stripe_subscription_status: ActiveValue<StripeSubscriptionStatus>,
     pub stripe_cancel_at: ActiveValue<Option<DateTime>>,
+    pub stripe_cancellation_reason: ActiveValue<Option<StripeCancellationReason>>,
 }
 
 impl Database {
@@ -51,6 +52,7 @@ impl Database {
                 stripe_subscription_id: params.stripe_subscription_id.clone(),
                 stripe_subscription_status: params.stripe_subscription_status.clone(),
                 stripe_cancel_at: params.stripe_cancel_at.clone(),
+                stripe_cancellation_reason: params.stripe_cancellation_reason.clone(),
                 ..Default::default()
             })
             .exec(&*tx)

crates/collab/src/db/tables/billing_subscription.rs

@@ -12,6 +12,7 @@ pub struct Model {
     pub stripe_subscription_id: String,
     pub stripe_subscription_status: StripeSubscriptionStatus,
     pub stripe_cancel_at: Option<DateTime>,
+    pub stripe_cancellation_reason: Option<StripeCancellationReason>,
     pub created_at: DateTime,
 }
 
@@ -73,3 +74,18 @@ impl StripeSubscriptionStatus {
         }
     }
 }
+
+/// The cancellation reason for a Stripe subscription.
+///
+/// [Stripe docs](https://docs.stripe.com/api/subscriptions/object#subscription_object-cancellation_details-reason)
+#[derive(Eq, PartialEq, Copy, Clone, Debug, EnumIter, DeriveActiveEnum, Hash, Serialize)]
+#[sea_orm(rs_type = "String", db_type = "String(StringLen::None)")]
+#[serde(rename_all = "snake_case")]
+pub enum StripeCancellationReason {
+    #[sea_orm(string_value = "cancellation_requested")]
+    CancellationRequested,
+    #[sea_orm(string_value = "payment_disputed")]
+    PaymentDisputed,
+    #[sea_orm(string_value = "payment_failed")]
+    PaymentFailed,
+}