fix: WASM sync writes through P2P consensus + local write-through

- Set require_consensus=true, allow_direct_writes=false for sync
- Write locally before P2P broadcast (read-your-own-writes for WASM)
- Broadcast to P2P so all validators get the same data via consensus
- Increase P2P event channel capacity from 256 to 4096

Author: echobt

bins/validator-node/src/challenge_storage.rs

@@ -105,8 +105,20 @@ impl StorageBackend for ChallengeStorageBackend {
                 signature,
             });
 
-            // Fire and forget - don't block WASM execution on P2P
-            tracing::info!(
+            // Write locally first so WASM can read-your-own-writes during sync
+            let storage_key = build_challenge_storage_key(challenge_id, key);
+            if let Err(e) = tokio::task::block_in_place(|| {
+                tokio::runtime::Handle::current().block_on(self.storage.put(
+                    storage_key,
+                    value.to_vec(),
+                    DPutOptions::default(),
+                ))
+            }) {
+                tracing::warn!(error = %e, "Failed to write locally before P2P broadcast");
+            }
+
+            // Broadcast via P2P so other validators also apply the write
+            tracing::debug!(
                 proposal_id = %hex::encode(&proposal_id[..8]),
                 challenge_id = %challenge_id,
                 key_len = key.len(),
@@ -115,7 +127,7 @@ impl StorageBackend for ChallengeStorageBackend {
             );
             let _ = tx.try_send(P2PCommand::Broadcast(msg));
 
-            // Also add the proposal to our local state (we don't receive our own broadcasts)
+            // Also add the proposal to our local state for vote tracking
             if let Some(local_tx) = &self.local_proposal_tx {
                 let local_proposal = StorageProposal {
                     proposal_id,

bins/validator-node/src/main.rs

@@ -465,7 +465,7 @@ async fn main() -> Result<()> {
     ));
 
     // Create event channel for network events
-    let (event_tx, mut event_rx) = tokio::sync::mpsc::channel::<NetworkEvent>(256);
+    let (event_tx, mut event_rx) = tokio::sync::mpsc::channel::<NetworkEvent>(4096);
 
     // Initialize P2P network
     let network = Arc::new(P2PNetwork::new(

bins/validator-node/src/wasm_executor.rs

@@ -1034,8 +1034,8 @@ impl WasmChallengeExecutor {
             challenge_id: module_path.to_string(),
             validator_id: "validator".to_string(),
             storage_host_config: StorageHostConfig {
-                allow_direct_writes: true,
-                require_consensus: false,
+                allow_direct_writes: false,
+                require_consensus: true,
                 ..self.config.storage_host_config.clone()
             },
             storage_backend: Arc::clone(&self.config.storage_backend),