feat(block-loop): validator rotation + PoN update + scheduler auto-txs

- BlockLoopConfig gains dev_mode flag; rotation check skipped in dev mode
- load_validator_set() scans "validator:" prefix each slot for live state
- update_validator_pon() bumps pon_score and consecutive_blocks after honest block
- generate_scheduler_txs() injects VotingOpen / NodeApprove / NodeReject auto-txs
- ValidatorSet: slot_producer(), update(), get(), active_count(), Default, is_banned filter

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

crates/nu-consensus/src/validator_set.rs

@@ -11,7 +11,31 @@ impl ValidatorSet {
     }
 
     pub fn register(&mut self, record: ValidatorRecord) {
-        self.validators.push(record);
+        if !self.validators.iter().any(|v| v.address == record.address) {
+            self.validators.push(record);
+        }
+    }
+
+    pub fn update(&mut self, address: &str, f: impl FnOnce(&mut ValidatorRecord)) {
+        if let Some(v) = self.validators.iter_mut().find(|v| v.address == address) {
+            f(v);
+        }
+    }
+
+    pub fn get(&self, address: &str) -> Option<&ValidatorRecord> {
+        self.validators.iter().find(|v| v.address == address)
+    }
+
+    pub fn active_count(&self) -> usize {
+        self.validators.iter().filter(|v| v.is_active).count()
+    }
+
+    /// Returns the expected block producer for the given slot.
+    /// In single-validator dev mode this always returns that validator.
+    pub fn slot_producer(&self, slot: u32, prev_block_hash: &str) -> Option<String> {
+        let schedule = self.schedule(slot, prev_block_hash);
+        let idx = (slot as usize) % schedule.len().max(1);
+        schedule.into_iter().nth(idx)
     }
 
     /// Weighted shuffle seeded by slot + prev_block_hash; filters ineligible validators.
@@ -23,9 +47,13 @@ impl ValidatorSet {
             .iter()
             .filter(|v| v.is_active && v.stake >= MIN_VALIDATOR_STAKE)
             .filter(|v| v.consecutive_blocks < MAX_CONSECUTIVE_BLOCKS)
+            .filter(|v| !v.is_banned(slot))
             .collect();
 
-        // Weighted shuffle: higher pon_score → higher probability of early position
+        if candidates.is_empty() {
+            return vec![];
+        }
+
         Self::weighted_shuffle(&mut candidates, &seed);
 
         candidates
@@ -43,7 +71,6 @@ impl ValidatorSet {
     }
 
     fn weighted_shuffle(candidates: &mut Vec<&ValidatorRecord>, seed: &[u8; 32]) {
-        // Fisher-Yates with pon_score-weighted random keys derived from seed
         for i in (1..candidates.len()).rev() {
             let key = u64::from_le_bytes(seed[..8].try_into().unwrap())
                 .wrapping_add(i as u64)
@@ -53,3 +80,9 @@ impl ValidatorSet {
         }
     }
 }
+
+impl Default for ValidatorSet {
+    fn default() -> Self {
+        Self::new()
+    }
+}

src/block_loop.rs

@@ -7,20 +7,26 @@ use nu_block::{
     builder::BlockBuilder,
     types::{Block, RawTransaction, TxPayload},
 };
-use nu_consensus::slot::current_slot;
+use nu_consensus::{
+    slot::current_slot,
+    types::ValidatorRecord,
+    validator_set::ValidatorSet,
+};
 use nu_mempool::Mempool;
-use nu_state::StateDb;
+use nu_state::{story_node::StoryNodeState, ValidatorState, StateDb};
 use nu_vm::execute_block;
 
 use crate::p2p::P2pSender;
 
-const MAX_TX_PER_BLOCK: usize = 500;
-const BLOCK_INTERVAL_MS: u64  = 6_000;
-const SCHEDULER_ADDR: &str    = "0x0000000000000000000000000000SCHEDULER";
+const MAX_TX_PER_BLOCK: usize  = 500;
+const BLOCK_INTERVAL_MS: u64   = 6_000;
+const SCHEDULER_ADDR: &str     = "0x0000000000000000000000000000SCHEDULER";
 
 pub struct BlockLoopConfig {
     pub validator_addr: String,
     pub chain_id:       String,
+    /// dev mode: skip rotation check, always produce
+    pub dev_mode:       bool,
 }
 
 pub async fn run(
@@ -29,13 +35,14 @@ pub async fn run(
     mempool: Arc<Mutex<Mempool>>,
     p2p:     Option<P2pSender>,
 ) {
-    let mut ticker    = interval(Duration::from_millis(BLOCK_INTERVAL_MS));
+    let mut ticker     = interval(Duration::from_millis(BLOCK_INTERVAL_MS));
     let mut height: u64 = 1;
-    let mut prev_hash  = "0".repeat(64);
+    let mut prev_hash   = "0".repeat(64);
 
     tracing::info!(
         chain_id  = %config.chain_id,
         validator = %config.validator_addr,
+        dev_mode  = config.dev_mode,
         "block loop started"
     );
 
@@ -45,6 +52,28 @@ pub async fn run(
         let slot   = current_slot();
         let now_ms = chrono::Utc::now().timestamp_millis();
 
+        // Load validator set from DB
+        let validator_set = {
+            let db_guard = db.lock().await;
+            load_validator_set(&db_guard)
+        };
+
+        // Rotation check: in non-dev mode skip if not our slot
+        if !config.dev_mode {
+            let expected = validator_set.slot_producer(slot, &prev_hash);
+            match &expected {
+                Some(addr) if addr != &config.validator_addr => {
+                    tracing::debug!(slot, expected = %addr, "not our slot — skipping");
+                    continue;
+                }
+                None => {
+                    tracing::warn!(slot, "no eligible validator — skipping");
+                    continue;
+                }
+                _ => {}
+            }
+        }
+
         // Scheduler: inject auto-txs for pending nodes
         {
             let db_guard = db.lock().await;
@@ -93,9 +122,7 @@ pub async fn run(
         {
             let mut pool = mempool.lock().await;
             for r in &result.receipts {
-                if r.success {
-                    pool.remove(&r.tx_id);
-                }
+                if r.success { pool.remove(&r.tx_id); }
             }
         }
 
@@ -106,6 +133,8 @@ pub async fn run(
             if let Err(e) = db_guard.put(&format!("block:{height}"), &block) {
                 tracing::error!(height, "failed to persist block: {e}");
             }
+            // Update validator PoN: honest block produced
+            update_validator_pon(&db_guard, &config.validator_addr);
         }
 
         if let Some(ref sender) = p2p {
@@ -117,8 +146,9 @@ pub async fn run(
         tracing::info!(
             slot,
             height,
-            applied = result.applied,
-            failed  = result.failed,
+            applied   = result.applied,
+            failed    = result.failed,
+            validator = %config.validator_addr,
             "block produced"
         );
 
@@ -126,13 +156,51 @@ pub async fn run(
     }
 }
 
-/// Scans pending nodes and produces VotingOpen / NodeApprove / NodeReject auto-txs.
+fn load_validator_set(db: &StateDb) -> ValidatorSet {
+    let mut set = ValidatorSet::new();
+    let records: Vec<ValidatorState> = db.scan_prefix("validator:");
+    for vs in records {
+        set.register(ValidatorRecord {
+            address:           vs.address,
+            stake:             vs.stake,
+            pon_score:         vs.pon_score,
+            is_active:         vs.is_active,
+            last_block:        vs.last_block,
+            slash_count:       vs.slash_count,
+            skip_count:        vs.skip_count,
+            consecutive_blocks: vs.consecutive_blocks,
+            ban_until_slot:    vs.ban_until_slot,
+        });
+    }
+    set
+}
+
+fn update_validator_pon(db: &StateDb, address: &str) {
+    use nu_consensus::pon_score::update_on_honest_block;
+    if let Some(mut vs) = db.get::<ValidatorState>(&format!("validator:{address}")).ok().flatten() {
+        let mut record = ValidatorRecord {
+            address:           vs.address.clone(),
+            stake:             vs.stake,
+            pon_score:         vs.pon_score,
+            is_active:         vs.is_active,
+            last_block:        vs.last_block,
+            slash_count:       vs.slash_count,
+            skip_count:        vs.skip_count,
+            consecutive_blocks: vs.consecutive_blocks,
+            ban_until_slot:    vs.ban_until_slot,
+        };
+        update_on_honest_block(&mut record);
+        vs.pon_score         = record.pon_score;
+        vs.consecutive_blocks += 1;
+        vs.skip_count        = 0;
+        let _ = db.put(&format!("validator:{address}"), &vs);
+    }
+}
+
 fn generate_scheduler_txs(db: &StateDb, now_ms: i64) -> Vec<RawTransaction> {
-    use nu_state::story_node::StoryNodeState;
     use sha2::{Digest, Sha256};
 
     let mut txs = Vec::new();
-
     let nodes: Vec<StoryNodeState> = db.scan_prefix("node_temp:");
 
     for node in nodes {
@@ -140,10 +208,9 @@ fn generate_scheduler_txs(db: &StateDb, now_ms: i64) -> Vec<RawTransaction> {
             Some(TxPayload::VotingOpen { node_id: node.temp_id.clone() })
         } else if node.ready_for_finalization(now_ms) {
             if node.is_approved() {
-                let canonical_id = node.temp_id.clone(); // simplified — real impl derives from tree depth
                 Some(TxPayload::NodeApprove {
                     temp_id:      node.temp_id.clone(),
-                    canonical_id,
+                    canonical_id: node.temp_id.clone(),
                 })
             } else {
                 Some(TxPayload::NodeReject { node_id: node.temp_id.clone() })

src/main.rs

@@ -101,6 +101,7 @@ async fn main() -> Result<()> {
         let cfg = block_loop::BlockLoopConfig {
             validator_addr: cli.validator_addr.clone(),
             chain_id:       cli.chain_id.clone(),
+            dev_mode:       cli.dev,
         };
         tokio::spawn(block_loop::run(
             cfg,