fix(gateway): load dotenv before federation tier gate (#1138)

apps/gateway/src/env.ts

@@ -0,0 +1,14 @@
+import { config } from 'dotenv';
+import { existsSync } from 'node:fs';
+import { homedir } from 'node:os';
+import { join, resolve } from 'node:path';
+
+// Load .env from daemon config dir (global install / daemon mode).
+// It takes precedence over file-based local-dev configuration.
+const daemonEnv = join(homedir(), '.config', 'mosaic', 'gateway', '.env');
+if (existsSync(daemonEnv)) config({ path: daemonEnv });
+
+// Load .env from monorepo root (cwd is apps/gateway when run via pnpm filter),
+// then fill any remaining values from apps/gateway/.env when present.
+config({ path: resolve(process.cwd(), '../../.env') });
+config();