Add project skeleton: CLI pipeline for CD digitization

Modular Python package with Typer CLI (scan/apply/process commands),
Pydantic data models, OCR via Tesseract, LLM-based tracklist parsing,
mutagen audio tagging, M3U playlist generation, and cover processing.
Includes 8 passing tests and ruff lint config.

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

tests/test_playlist.py

@@ -0,0 +1,37 @@
+"""Tests für die Playlist-Generierung."""
+
+from pathlib import Path
+
+from musiksammlung.models import Album, Disc, Track
+from musiksammlung.playlist import generate_playlist
+
+
+def test_generate_playlist_single_disc(tmp_path: Path):
+    """Erzeugt eine M3U-Playlist für ein Single-CD-Album."""
+    album = Album(
+        artist="Artist",
+        album="TestAlbum",
+        year=2000,
+        discs=[
+            Disc(
+                disc_number=1,
+                tracks=[
+                    Track(track_number=1, title="Song Eins"),
+                    Track(track_number=2, title="Song Zwei"),
+                ],
+            )
+        ],
+    )
+
+    # Dummy-Audiodateien anlegen
+    (tmp_path / "01 Song Eins.flac").touch()
+    (tmp_path / "02 Song Zwei.flac").touch()
+
+    playlist_path = generate_playlist(album, tmp_path)
+    assert playlist_path.exists()
+    content = playlist_path.read_text()
+    assert "#EXTM3U" in content
+    assert "01 Song Eins.flac" in content
+    assert "02 Song Zwei.flac" in content
+    # Kein CD-Prefix bei Single-Disc
+    assert "CD1/" not in content