feat: fix DWN sync to use federation peers and standard port

- DWN sync now uses federation node list instead of old peer list
- Fix sync URL to use port 80 (nginx) instead of 5678 (direct backend)
- DWN /dwn endpoint now accessible without auth for peer sync
- Support both message formats: {message:{}} and {messages:[{}]}
- Replace request["message"] with unified message variable

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

core/archipelago/src/api/rpc/dwn.rs

@@ -1,7 +1,7 @@
 use super::RpcHandler;
+use crate::federation;
 use crate::network::dwn_store::{DwnStore, MessageQuery, ProtocolDefinition};
 use crate::network::dwn_sync;
-use crate::peers;
 use anyhow::Result;
 
 impl RpcHandler {
@@ -32,11 +32,11 @@ impl RpcHandler {
 
     /// Trigger DWN sync with connected peers.
     pub(super) async fn handle_dwn_sync(&self) -> Result<serde_json::Value> {
-        let peer_list = peers::load_peers(&self.config.data_dir).await?;
-        let onions: Vec<String> = peer_list
+        let nodes = federation::load_nodes(&self.config.data_dir).await?;
+        let onions: Vec<String> = nodes
             .iter()
-            .filter(|p| !p.onion.is_empty())
-            .map(|p| p.onion.clone())
+            .filter(|n| !n.onion.is_empty() && n.trust_level != federation::TrustLevel::Untrusted)
+            .map(|n| n.onion.clone())
             .collect();
 
         let state = dwn_sync::sync_with_peers(&self.config.data_dir, &onions).await?;