Initial open-source self-hosted Songs2YT edition

lib/edition.ts

@@ -0,0 +1,11 @@
+import { Plan } from "@prisma/client";
+
+/** Self-hosted / open-source edition: unlimited quotas and Pro features unlocked. */
+export function isSelfHostedEdition(): boolean {
+  return process.env.S2YT_EDITION === "selfhosted";
+}
+
+/** Pro-gated features (API keys, playlists, etc.) are available. */
+export function hasProFeatures(plan: Plan): boolean {
+  return isSelfHostedEdition() || plan === "PREMIUM";
+}