feat: bootstrap NAS music deduper

am_deduper/metadata.py

@@ -0,0 +1,24 @@
+from __future__ import annotations
+
+from pathlib import Path
+
+try:
+    from tinytag import TinyTag
+except ImportError:  # optional until metadata phase is invoked
+    TinyTag = None
+
+
+def read_metadata(path: Path) -> dict:
+    if TinyTag is None:
+        return {}
+    tag = TinyTag.get(str(path), image=False)
+    return {
+        "duration": tag.duration,
+        "artist": tag.artist,
+        "title": tag.title,
+        "album": tag.album,
+        "format": path.suffix.lower().lstrip("."),
+        "bitrate": int(tag.bitrate) if tag.bitrate else None,
+        "sample_rate": int(tag.samplerate) if tag.samplerate else None,
+        "bit_depth": int(tag.bitdepth) if tag.bitdepth else None,
+    }