Add crop manager for staging and training image lifecycle

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

vigilar/detection/crop_manager.py

@@ -0,0 +1,48 @@
+"""Manage detection crop images for training and staging."""
+
+import logging
+import shutil
+import time
+from pathlib import Path
+
+import cv2
+import numpy as np
+
+log = logging.getLogger(__name__)
+
+
+class CropManager:
+    def __init__(self, staging_dir: str, training_dir: str):
+        self._staging_dir = Path(staging_dir)
+        self._training_dir = Path(training_dir)
+
+    def save_staging_crop(self, crop: np.ndarray, species: str, camera_id: str) -> str:
+        self._staging_dir.mkdir(parents=True, exist_ok=True)
+        timestamp = int(time.time() * 1000)
+        filename = f"{species}_{camera_id}_{timestamp}.jpg"
+        filepath = self._staging_dir / filename
+        cv2.imwrite(str(filepath), crop)
+        return str(filepath)
+
+    def promote_to_training(self, staging_path: str, pet_name: str) -> str:
+        pet_dir = self._training_dir / pet_name.lower()
+        pet_dir.mkdir(parents=True, exist_ok=True)
+        src = Path(staging_path)
+        dst = pet_dir / src.name
+        shutil.move(str(src), str(dst))
+        return str(dst)
+
+    def cleanup_expired(self, retention_days: int = 7) -> int:
+        if not self._staging_dir.exists():
+            return 0
+
+        cutoff = time.time() - retention_days * 86400
+        deleted = 0
+        for filepath in self._staging_dir.iterdir():
+            if filepath.is_file() and filepath.stat().st_mtime < cutoff:
+                filepath.unlink()
+                deleted += 1
+
+        if deleted:
+            log.info("Cleaned up %d expired staging crops", deleted)
+        return deleted