Write progress.ndjson and live.json to logs dir during pipeline runs

Every PipelineEvent is now logged as a JSON envelope with timestamp,
run_id, and event fields — matching the Kilroy reference implementation.

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

crates/attractor/src/cli/run.rs

@@ -3,7 +3,7 @@ use std::sync::{Arc, Mutex};
 use std::time::Instant;
 
 use anyhow::bail;
-use chrono::Local;
+use chrono::{Local, Utc};
 use terminal::Styles;
 
 use crate::checkpoint::Checkpoint;
@@ -93,6 +93,39 @@ pub async fn run_command(args: RunArgs, styles: &'static Styles) -> anyhow::Resu
         }
     });
 
+    // NDJSON progress log + live.json snapshot
+    {
+        let ndjson_path = logs_dir.join("progress.ndjson");
+        let live_path = logs_dir.join("live.json");
+        let run_id = Arc::new(Mutex::new(String::new()));
+        let run_id_clone = Arc::clone(&run_id);
+        emitter.on_event(move |event| {
+            if let crate::event::PipelineEvent::PipelineStarted { id, .. } = event {
+                *run_id_clone.lock().unwrap() = id.clone();
+            }
+            let envelope = serde_json::json!({
+                "timestamp": Utc::now().to_rfc3339_opts(chrono::SecondsFormat::Millis, true),
+                "run_id": *run_id_clone.lock().unwrap(),
+                "event": event,
+            });
+            // Append to progress.ndjson
+            if let Ok(line) = serde_json::to_string(&envelope) {
+                use std::io::Write;
+                if let Ok(mut f) = std::fs::OpenOptions::new()
+                    .create(true)
+                    .append(true)
+                    .open(&ndjson_path)
+                {
+                    let _ = writeln!(f, "{line}");
+                }
+            }
+            // Overwrite live.json
+            if let Ok(pretty) = serde_json::to_string_pretty(&envelope) {
+                let _ = std::fs::write(&live_path, pretty);
+            }
+        });
+    }
+
     if args.verbose >= 2 {
         emitter.on_event(move |event| {
             eprint!("{}", format_event_detail(event, styles));

crates/attractor/tests/cli.rs

@@ -117,3 +117,54 @@ fn dry_run_styled() {
         .assert()
         .success();
 }
+
+// -- NDJSON logging ----------------------------------------------------------
+
+#[test]
+fn dry_run_writes_ndjson_and_live_json() {
+    let tmp = tempfile::tempdir().unwrap();
+    let logs_dir = tmp.path().join("logs");
+
+    attractor()
+        .args([
+            "run",
+            "--dry-run",
+            "--auto-approve",
+            "--logs-dir",
+            logs_dir.to_str().unwrap(),
+            "../../test/simple.dot",
+        ])
+        .assert()
+        .success();
+
+    // progress.ndjson must exist and contain valid JSON lines
+    let ndjson_path = logs_dir.join("progress.ndjson");
+    assert!(ndjson_path.exists(), "progress.ndjson should exist");
+    let ndjson_content = std::fs::read_to_string(&ndjson_path).unwrap();
+    let lines: Vec<&str> = ndjson_content.lines().collect();
+    assert!(!lines.is_empty(), "progress.ndjson should have at least one line");
+
+    // Every line must be valid JSON with timestamp, run_id, and event keys
+    let first_line: serde_json::Value = serde_json::from_str(lines[0]).unwrap();
+    assert!(first_line.get("timestamp").is_some(), "line should have timestamp");
+    assert!(first_line.get("run_id").is_some(), "line should have run_id");
+    assert!(first_line.get("event").is_some(), "line should have event");
+
+    // First event should be PipelineStarted
+    let first_event = &first_line["event"];
+    assert!(first_event.get("PipelineStarted").is_some(), "first event should be PipelineStarted");
+
+    // run_id should be non-empty after PipelineStarted
+    let last_line: serde_json::Value = serde_json::from_str(lines[lines.len() - 1]).unwrap();
+    let run_id = last_line["run_id"].as_str().unwrap();
+    assert!(!run_id.is_empty(), "run_id should be non-empty");
+
+    // live.json must exist and contain valid JSON matching the last NDJSON line
+    let live_path = logs_dir.join("live.json");
+    assert!(live_path.exists(), "live.json should exist");
+    let live_content: serde_json::Value =
+        serde_json::from_str(&std::fs::read_to_string(&live_path).unwrap()).unwrap();
+    assert!(live_content.get("timestamp").is_some());
+    assert!(live_content.get("run_id").is_some());
+    assert!(live_content.get("event").is_some());
+}