fix docker

.env.production.example

@@ -2,10 +2,17 @@
 # Production environment for the Docker stack.
 #
 #   cp .env.production.example .env.production
-#   docker compose run --rm --no-deps app php artisan key:generate --show
+#   # fill in at least DB_PASSWORD below — docker-compose.yml refuses to
+#   # interpolate at all without it, even for the next command
+#   docker compose --env-file .env.production run --rm --no-deps app php artisan key:generate --show
 #
 # Everything the containers need is here; docker-compose.yml sets the database,
 # cache, session and queue drivers itself so they cannot drift.
+#
+# This file only matters for a manual deploy. A platform that injects its own
+# "Environment Variables" (Dokploy, Coolify, ...) exports them as real process
+# environment variables instead, which docker-compose.yml's `${VAR}`
+# interpolation reads directly — no file needed on the server at all.
 ###############################################################################
 
 APP_NAME="Pireon Admin"