scripts: add a script to find music with no album artist

scripts/cmds/find-no-album-artist.fish

@@ -0,0 +1,16 @@
+#!/usr/bin/env fish
+
+set filter 'pan=mono|c0=0.5*FL+-0.5*FR,silenceremove=start_periods=1:detection=peak'
+
+for f in (find . -type f \( -name "*.ogg"  -o \
+                            -name "*.flac" -o \
+                            -name "*.mp3"  -o \
+                            -name "*.opus" \))
+	set out (ffprobe "$f" 2>/dev/null | rg "album_artist")
+
+	if test ! "$out"
+		echo "$f has no album artist tag"
+	end
+end
+
+## EOF