feat: add pox_stx_threshold amount to /new_block event data

stacks-signer/src/client/stacks_client.rs

@@ -1143,6 +1143,7 @@ mod tests {
                 stacked_amt: rand::thread_rng().next_u64() as u128,
                 weight: 1,
             }]),
+            pox_ustx_threshold: None,
         };
         let stackers_response = GetStackersResponse {
             stacker_set: stacker_set.clone(),

stackslib/src/chainstate/coordinator/tests.rs

@@ -511,6 +511,7 @@ impl RewardSetProvider for StubbedRewardSetProvider {
                 missed_reward_slots: vec![],
             },
             signers: None,
+            pox_ustx_threshold: None,
         })
     }
 

stackslib/src/chainstate/stacks/boot/mod.rs

@@ -213,6 +213,33 @@ fn hex_deserialize<'de, D: serde::Deserializer<'de>>(
     Ok(bytes)
 }
 
+fn serialize_optional_u128_as_string<S>(
+    value: &Option<u128>,
+    serializer: S,
+) -> Result<S::Ok, S::Error>
+where
+    S: serde::Serializer,
+{
+    match value {
+        Some(v) => serializer.serialize_str(&v.to_string()),
+        None => serializer.serialize_none(),
+    }
+}
+
+fn deserialize_optional_u128_from_string<'de, D>(deserializer: D) -> Result<Option<u128>, D::Error>
+where
+    D: serde::Deserializer<'de>,
+{
+    let s: Option<String> = Option::deserialize(deserializer)?;
+    match s {
+        Some(str_val) => str_val
+            .parse::<u128>()
+            .map(Some)
+            .map_err(serde::de::Error::custom),
+        None => Ok(None),
+    }
+}
+
 fn serialize_u128_as_string<S>(value: &u128, serializer: S) -> Result<S::Ok, S::Error>
 where
     S: serde::Serializer,
@@ -248,6 +275,11 @@ pub struct RewardSet {
     #[serde(skip_serializing_if = "Option::is_none", default)]
     // only generated for nakamoto reward sets
     pub signers: Option<Vec<NakamotoSignerEntry>>,
+    #[serde(
+        serialize_with = "serialize_optional_u128_as_string",
+        deserialize_with = "deserialize_optional_u128_from_string"
+    )]
+    pub pox_ustx_threshold: Option<u128>,
 }
 
 #[derive(Debug, PartialEq, Clone, Serialize, Deserialize)]
@@ -280,6 +312,7 @@ impl RewardSet {
                 missed_reward_slots: vec![],
             },
             signers: None,
+            pox_ustx_threshold: None,
         }
     }
 
@@ -863,6 +896,7 @@ impl StacksChainState {
                 missed_reward_slots: missed_slots,
             },
             signers: signer_set,
+            pox_ustx_threshold: Some(threshold),
         }
     }