Update .env.example

.env.example

@@ -1,8 +1,20 @@
-# ── Database (Postgres) ──────────────────────────────────────────────────────
+# ── PostgreSQL Database Settings ─────────────────────────────────────────────
 DB_USER=postgres
-DB_PASS=supersecret
+#   The username your bot will use to connect to Postgres.
-DB_NAME=lnbitsdb
+#   Default Postgres user is “postgres”, but you can lock it down.
-DATABASE_URL=postgresql://${DB_USER}:${DB_PASS}@db:5432/${DB_NAME}
 
-# ── Flask UI ──────────────────────────────────────────────────────────────────
+DB_PASS=supersecret
+#   The password for that DB_USER. Keep this strong and secret.
+
+DB_NAME=lnbitsdb
+#   The name of the database that holds your `config`, `plans`, and `subscriptions` tables.
+#   On first run the `lnbitsdb` DB will be created automatically by the Postgres container.
+
+DATABASE_URL=postgresql://${DB_USER}:${DB_PASS}@db:5432/${DB_NAME}
+#   The full SQLAlchemy connection string your bot uses to open the database.
+#   NOTE: “db” here is the service name from docker-compose, not “localhost”.
+
+# ── Flask Web UI Settings ────────────────────────────────────────────────────
 FLASK_SECRET=someRandomStringForSessions
+#   A random string (32+ chars) used by Flask to sign session cookies.
+#   Change this to something unguessable before going into production.