changed genre scanning to parse multiple genres, updated db to accommodate.

backend/database/sql/queries/audio_files.sql

@@ -80,7 +80,13 @@ SELECT
     r.track_number,
     r.disc_number,
     COALESCE(rg.name, '') AS album,
-    COALESCE(r.genre, '') AS genre,
+    CAST(COALESCE(
+        (SELECT GROUP_CONCAT(g.name, '||')
+         FROM recording_genres rg_sub
+         JOIN genres g ON rg_sub.genre_id = g.id
+         WHERE rg_sub.recording_id = r.id),
+        ''
+    ) AS TEXT) AS genre,
     COALESCE(r.year, 0) AS year,
     COALESCE(r.composer, '') AS composer,
     COALESCE(ft.extension, '') AS file_type

backend/database/sql/queries/genres.sql

@@ -0,0 +1,24 @@
+-- name: UpsertGenre :one
+INSERT INTO genres (name) VALUES (?)
+ON CONFLICT(name) DO UPDATE SET name = name
+RETURNING *;
+
+-- name: CreateRecordingGenre :exec
+INSERT OR IGNORE INTO recording_genres (recording_id, genre_id)
+VALUES (?, ?);
+
+-- name: DeleteRecordingGenres :exec
+DELETE FROM recording_genres
+WHERE recording_id = ?;
+
+-- name: GetGenresByRecordingID :many
+SELECT g.*
+FROM genres g
+JOIN recording_genres rg ON g.id = rg.genre_id
+WHERE rg.recording_id = ?;
+
+-- name: DeleteAllRecordingGenres :exec
+DELETE FROM recording_genres;
+
+-- name: DeleteAllGenres :exec
+DELETE FROM genres;