Omit outp oint if not provieded

src/entry.ts

@@ -17,7 +17,7 @@ export class MediaEntry extends Entry {
 		return /* HTML */ `<entry
 			producer="${this.producer.id}"
 			in="${this.in_point}"
-			out="${this.out_point}"
+			${this.out_point ? `out="${this.out_point}"` : ""}
 		></entry>`;
 	}
 }