add tx as well

schema.graphql

@@ -469,6 +469,7 @@ type VeDelegation @entity {
   expireTime: BigInt!
   block: Int!
   timestamp: Int!
+  tx: String!
 }
 
 type VeOCEAN @entity {

src/mappings/utils/veUtils.ts

@@ -134,6 +134,7 @@ export function getveDelegation(id: string): VeDelegation {
     veDelegation.delegator = ''
     veDelegation.block = 0
     veDelegation.timestamp = 0
+    veDelegation.tx = ''
     veDelegation.save()
   }
   return veDelegation

src/mappings/veDelegation.ts

@@ -25,6 +25,7 @@ export function handleDelegation(event: DelegateBoost): void {
   veDelegation.expireTime = _expireTime
   veDelegation.block = event.block.number.toI32()
   veDelegation.timestamp = event.block.timestamp.toI32()
+  veDelegation.tx = event.transaction.hash.toHex()
   veDelegation.save()
 }
 
@@ -44,6 +45,7 @@ export function handleExtendBoost(event: ExtendBoost): void {
   veDelegation.cancelTime = _cancelTime
   veDelegation.expireTime = _expireTime
   veDelegation.timestamp = event.block.timestamp.toI32()
+  veDelegation.tx = event.transaction.hash.toHex()
   veDelegation.save()
 }