feat(run): auto-save corpus samples + annotated FIRE screenshots

- samples/: full frame saved every time accepted colour changes (enough
  diversity for the labelled corpus, no constant-N-seconds flood).
- logs/fires/: annotated frame saved on every BUY/SELL trigger, attached
  to the Discord/Telegram Alert so the push includes a visual.

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

src/atm/main.py

@@ -377,6 +377,12 @@ def run_live(cfg, duration_s=None, capture_stub: bool = False) -> None:
     start = time.monotonic()
     heartbeat_due = start + cfg.heartbeat_min * 60
     levels_extractor = None
+    last_saved_color: str | None = None
+    samples_dir = Path("samples")
+    samples_dir.mkdir(exist_ok=True)
+    fires_dir = Path("logs") / "fires"
+    fires_dir.mkdir(parents=True, exist_ok=True)
+    import cv2  # type: ignore[import-untyped]
 
     try:
         while duration_s is None or (time.monotonic() - start) < duration_s:
@@ -400,11 +406,31 @@ def run_live(cfg, duration_s=None, capture_stub: bool = False) -> None:
                     "ts": now, "event": "tick",
                     "color": res.color, "state": tr.next.value, "reason": tr.reason,
                 })
+                # corpus: save full frame on each new distinct color for later labeling
+                if res.color != last_saved_color:
+                    ts_str = datetime.fromtimestamp(now).strftime("%Y%m%d_%H%M%S")
+                    sample_path = samples_dir / f"{ts_str}_{res.color}.png"
+                    try:
+                        cv2.imwrite(str(sample_path), frame)
+                    except Exception as exc:
+                        audit.log({"ts": now, "event": "sample_save_failed", "error": str(exc)})
+                    last_saved_color = res.color
+                # FIRE: annotate frame + save, attach to alert
                 if tr.trigger and not tr.locked:
+                    ts_str = datetime.fromtimestamp(now).strftime("%Y%m%d_%H%M%S")
+                    fire_path = fires_dir / f"{ts_str}_{tr.trigger}.png"
+                    try:
+                        annotated = frame.copy()
+                        x, y, w, h = cfg.dot_roi.x, cfg.dot_roi.y, cfg.dot_roi.w, cfg.dot_roi.h
+                        cv2.rectangle(annotated, (x, y), (x + w, y + h), (0, 255, 255), 2)
+                        cv2.imwrite(str(fire_path), annotated)
+                    except Exception:
+                        fire_path = None
                     notifier.send(Alert(
                         kind="trigger",
                         title=f"{tr.trigger} signal",
-                        body=f"@ {now}",
+                        body=f"@ {datetime.fromtimestamp(now).isoformat(timespec='seconds')}",
+                        image_path=fire_path,
                         direction=tr.trigger,
                     ))
                     levels_extractor = LevelsExtractor(cfg, tr.trigger, now)