feat(iota-graphql-rpc): expose treasury cap id (#3557)

crates/iota-graphql-rpc/schema.graphql

@@ -1169,6 +1169,10 @@ type Epoch {
 	"""
 	iotaTotalSupply: Int
 	"""
+	The treasury-cap id.
+	"""
+	iotaTreasuryCapId: IotaAddress
+	"""
 	Details of the system that are decided during genesis.
 	"""
 	systemParameters: SystemParameters

crates/iota-graphql-rpc/src/types/system_state_summary.rs

@@ -6,8 +6,8 @@ use async_graphql::*;
 use iota_types::iota_system_state::iota_system_state_summary::IotaSystemStateSummary as NativeSystemStateSummary;
 
 use crate::types::{
-    big_int::BigInt, gas::GasCostSummary, safe_mode::SafeMode, storage_fund::StorageFund,
-    system_parameters::SystemParameters, uint53::UInt53,
+    big_int::BigInt, gas::GasCostSummary, iota_address::IotaAddress, safe_mode::SafeMode,
+    storage_fund::StorageFund, system_parameters::SystemParameters, uint53::UInt53,
 };
 
 #[derive(Clone, Debug)]
@@ -59,6 +59,11 @@ impl SystemStateSummary {
         Some(self.native.iota_total_supply)
     }
 
+    /// The treasury-cap id.
+    async fn iota_treasury_cap_id(&self) -> Option<IotaAddress> {
+        Some(self.native.iota_treasury_cap_id.into())
+    }
+
     /// Details of the system that are decided during genesis.
     async fn system_parameters(&self) -> Option<SystemParameters> {
         Some(SystemParameters {

crates/iota-graphql-rpc/tests/snapshots/snapshot_tests__schema_sdl_export.snap

@@ -1173,6 +1173,10 @@ type Epoch {
 	"""
 	iotaTotalSupply: Int
 	"""
+	The treasury-cap id.
+	"""
+	iotaTreasuryCapId: IotaAddress
+	"""
 	Details of the system that are decided during genesis.
 	"""
 	systemParameters: SystemParameters