feat: DID persistence + federation node names in sync

Part 1 — DID Persistence:
- Deploy script creates /var/lib/archipelago/identity/ directory
- First-boot script creates identity dir with proper ownership
- Identity load now logs pubkey to confirm persistence across restarts

Part 2 — Node Names:
- NodeStateSnapshot includes node_name field
- build_local_state() passes server name to sync responses
- update_node_state() stores peer's announced name on the FederatedNode
- Names propagate automatically during federation.sync-state

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

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

@@ -328,8 +328,9 @@ impl RpcHandler {
 
         let tor_active = data.server_info.tor_address.is_some();
 
+        let server_name = data.server_info.name.clone().filter(|n| !n.is_empty());
         let state = federation::build_local_state(
-            apps, 0.0, 0, 0, 0, 0, 0, tor_active,
+            apps, 0.0, 0, 0, 0, 0, 0, tor_active, server_name,
         );
 
         Ok(serde_json::to_value(&state)?)

core/archipelago/src/federation.rs

@@ -53,6 +53,8 @@ pub struct FederatedNode {
 pub struct NodeStateSnapshot {
     pub timestamp: String,
     #[serde(default)]
+    pub node_name: Option<String>,
+    #[serde(default)]
     pub apps: Vec<AppStatus>,
     #[serde(default)]
     pub cpu_usage_percent: Option<f64>,
@@ -184,6 +186,12 @@ pub async fn update_node_state(
     let mut nodes = load_nodes(data_dir).await?;
     if let Some(node) = nodes.iter_mut().find(|n| n.did == did) {
         node.last_seen = Some(state.timestamp.clone());
+        // Update node name from sync if provided (peer announced their name)
+        if let Some(ref name) = state.node_name {
+            if !name.is_empty() {
+                node.name = Some(name.clone());
+            }
+        }
         node.last_state = Some(state);
         save_nodes(data_dir, &nodes).await?;
     }
@@ -495,9 +503,11 @@ pub fn build_local_state(
     disk_total: u64,
     uptime: u64,
     tor_active: bool,
+    server_name: Option<String>,
 ) -> NodeStateSnapshot {
     NodeStateSnapshot {
         timestamp: chrono::Utc::now().to_rfc3339(),
+        node_name: server_name,
         apps,
         cpu_usage_percent: Some(cpu),
         mem_used_bytes: Some(mem_used),
@@ -813,9 +823,11 @@ mod tests {
             500_000_000_000,
             3600,
             true,
+            Some("Test Node".to_string()),
         );
         assert_eq!(state.apps.len(), 1);
         assert_eq!(state.cpu_usage_percent, Some(25.5));
         assert_eq!(state.tor_active, Some(true));
+        assert_eq!(state.node_name, Some("Test Node".to_string()));
     }
 }

core/archipelago/src/identity.rs

@@ -35,7 +35,10 @@ impl NodeIdentity {
             let arr: [u8; 32] = bytes
                 .try_into()
                 .map_err(|_| anyhow::anyhow!("Invalid node key length"))?;
-            SigningKey::from_bytes(&arr)
+            let key = SigningKey::from_bytes(&arr);
+            let pubkey_hex = hex::encode(key.verifying_key().as_bytes());
+            tracing::info!("Loaded existing node identity (pubkey: {}...)", &pubkey_hex[..16]);
+            key
         } else {
             let signing_key = SigningKey::generate(&mut OsRng);
             fs::write(&key_path, signing_key.to_bytes())

core/archipelago/src/transport/delta.rs

@@ -195,6 +195,7 @@ mod tests {
     fn sample_snapshot_a() -> NodeStateSnapshot {
         NodeStateSnapshot {
             timestamp: "2026-03-16T12:00:00Z".to_string(),
+            node_name: Some("Test Node A".to_string()),
             apps: vec![
                 AppStatus {
                     id: "bitcoin-knots".to_string(),
@@ -225,6 +226,7 @@ mod tests {
     fn sample_snapshot_b() -> NodeStateSnapshot {
         NodeStateSnapshot {
             timestamp: "2026-03-16T12:05:00Z".to_string(),
+            node_name: Some("Test Node A".to_string()),
             apps: vec![
                 AppStatus {
                     id: "bitcoin-knots".to_string(),