feat(billing-platform): add ChargeService.list_refunds_by_invoice endpoint (REVENG-157)

proto/sentry_protos/billing/v1/services/charge/v1/charge.proto

@@ -45,4 +45,9 @@ message PlatformRefund {
   optional string reason = 4;
   // Unix epoch seconds when the refund was recorded by the platform.
   int64 date_added_st = 5;
+  // Stripe id of the ``PlatformCharge`` this refund applies to. Mirrors
+  // Stripe's own ``refund.charge`` wire field. Lets callers disambiguate
+  // refunds in flat responses like ``ListRefundsByInvoiceResponse`` when
+  // an invoice has more than one charge (e.g. retries, partial capture).
+  string stripe_charge_id = 6;
 }

proto/sentry_protos/billing/v1/services/charge/v1/endpoint_list_refunds.proto

@@ -0,0 +1,18 @@
+syntax = "proto3";
+
+package sentry_protos.billing.v1.services.charge.v1;
+
+import "sentry_protos/billing/v1/services/charge/v1/charge.proto";
+
+// Lists every recorded refund associated with the charges for a single
+// platform invoice. Callers in the presentation layer use this to render
+// invoice-level refund state without crossing the charge service boundary.
+message ListRefundsByInvoiceRequest {
+  uint64 invoice_id = 1;
+}
+
+message ListRefundsByInvoiceResponse {
+  // Refunds ordered by ``date_added_st`` ascending. Empty when the invoice
+  // has no refunds.
+  repeated PlatformRefund refunds = 1;
+}

rust/src/sentry_protos.billing.v1.services.charge.v1.rs

@@ -60,6 +60,12 @@ pub struct PlatformRefund {
     /// Unix epoch seconds when the refund was recorded by the platform.
     #[prost(int64, tag = "5")]
     pub date_added_st: i64,
+    /// Stripe id of the `PlatformCharge` this refund applies to. Mirrors
+    /// Stripe's own `refund.charge` wire field. Lets callers disambiguate
+    /// refunds in flat responses like `ListRefundsByInvoiceResponse` when
+    /// an invoice has more than one charge (e.g. retries, partial capture).
+    #[prost(string, tag = "6")]
+    pub stripe_charge_id: ::prost::alloc::string::String,
 }
 #[derive(Clone, PartialEq, Eq, Hash, ::prost::Message)]
 pub struct CaptureChargeRequest {
@@ -162,6 +168,21 @@ pub struct ListChargesForInvoiceResponse {
     #[prost(message, repeated, tag = "1")]
     pub charges: ::prost::alloc::vec::Vec<Charge>,
 }
+/// Lists every recorded refund associated with the charges for a single
+/// platform invoice. Callers in the presentation layer use this to render
+/// invoice-level refund state without crossing the charge service boundary.
+#[derive(Clone, Copy, PartialEq, Eq, Hash, ::prost::Message)]
+pub struct ListRefundsByInvoiceRequest {
+    #[prost(uint64, tag = "1")]
+    pub invoice_id: u64,
+}
+#[derive(Clone, PartialEq, ::prost::Message)]
+pub struct ListRefundsByInvoiceResponse {
+    /// Refunds ordered by `date_added_st` ascending. Empty when the invoice
+    /// has no refunds.
+    #[prost(message, repeated, tag = "1")]
+    pub refunds: ::prost::alloc::vec::Vec<PlatformRefund>,
+}
 /// Records platform refunds for a Stripe charge from a webhook payload.
 /// Mirrors the contents of `stripe_charge.refunds` as `PlatformRefund`
 /// rows idempotently keyed by Stripe refund id, and syncs the aggregate