Add GET /api/v1/statistics/soundtracks with every soundtrack and its songs

The other soundtrack statistics are capped at 100, so a client that shows every soundtrack (the MusicPlayer statistics tab) had no way to get them all. This one has no limit and is sorted by name.

internal/server/openapi_test.go

@@ -103,6 +103,7 @@ func TestOpenAPIDocumentsTheV1API(t *testing.T) {
 		"GET /api/v1/soundtracks/{uuid}",
 		"GET /api/v1/statistics/songs/least-played",
 		"GET /api/v1/statistics/songs/most-played",
+		"GET /api/v1/statistics/soundtracks",
 		"GET /api/v1/statistics/soundtracks/last-played",
 		"GET /api/v1/statistics/soundtracks/least-played",
 		"GET /api/v1/statistics/soundtracks/most-played",
@@ -225,6 +226,7 @@ func TestResponsesMatchOpenAPI(t *testing.T) {
 		v.check(http.MethodGet, "/api/v1/statistics"+path+"?limit=5", "", http.StatusOK)
 	}
 	v.check(http.MethodGet, "/api/v1/statistics/soundtracks/never-played", "", http.StatusOK)
+	v.check(http.MethodGet, "/api/v1/statistics/soundtracks", "", http.StatusOK)
 	v.check(http.MethodGet, "/api/v1/statistics/summary", "", http.StatusOK)
 
 	// Sync, including the locked state and the result after it finishes.
@@ -254,6 +256,7 @@ func TestResponsesMatchOpenAPI(t *testing.T) {
 	stats.handler = stats.server.RegisterRoutes()
 	vs := newSpecValidator(t, stats)
 	vs.check(http.MethodGet, "/api/v1/statistics/soundtracks/most-played", "", http.StatusOK)
+	vs.check(http.MethodGet, "/api/v1/statistics/soundtracks", "", http.StatusOK)
 	vs.check(http.MethodGet, "/api/v1/statistics/summary", "", http.StatusOK)
 
 	// Every documented operation was checked at least once (statistics and tokens use other environments).