fix: attack chain node linking and disable input while pentest runs

Link attack chain nodes to previous iteration's nodes via parent_node_ids
so the DAG graph shows proper hierarchy instead of flat dots. Disable the
chat input while a pentest session is running since messages have no effect.

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

compliance-agent/src/pentest/orchestrator.rs

@@ -172,6 +172,7 @@ impl PentestOrchestrator {
         let mut total_findings = 0u32;
         let mut total_tool_calls = 0u32;
         let mut total_successes = 0u32;
+        let mut prev_node_ids: Vec<String> = Vec::new();
 
         for _iteration in 0..max_iterations {
             let response = self
@@ -233,6 +234,8 @@ impl PentestOrchestrator {
                         tool_call_id: None,
                     });
 
+                    let mut current_batch_node_ids: Vec<String> = Vec::new();
+
                     for tc in &tool_calls {
                         total_tool_calls += 1;
                         let node_id = uuid::Uuid::new_v4().to_string();
@@ -244,9 +247,12 @@ impl PentestOrchestrator {
                             tc.arguments.clone(),
                             String::new(),
                         );
+                        // Link to previous iteration's nodes
+                        node.parent_node_ids = prev_node_ids.clone();
                         node.status = AttackNodeStatus::Running;
                         node.started_at = Some(chrono::Utc::now());
                         let _ = self.db.attack_chain_nodes().insert_one(&node).await;
+                        current_batch_node_ids.push(node_id.clone());
 
                         let _ = self.event_tx.send(PentestEvent::ToolStart {
                             node_id: node_id.clone(),
@@ -337,6 +343,9 @@ impl PentestOrchestrator {
                         });
                     }
 
+                    // Advance parent links so next iteration's nodes connect to this batch
+                    prev_node_ids = current_batch_node_ids;
+
                     if let Some(sid) = session.id {
                         let _ = self
                             .db