🔧 use .env instead of json config files

.env.example

@@ -0,0 +1,18 @@
+## Google Cloud Platform Service Account
+GCP_SERVICE_ACCOUNT_PRIVATE_KEY=
+GCP_SERVICE_ACCOUNT_CLIENT_ID=
+GCP_SERVICE_ACCOUNT_CLIENT_EMAIL=
+GSHEET_ID=
+
+## Discord
+DISCORD_TOKEN=
+DISCORD_CLIENTID=
+DISCORD_GUILDID=
+
+## Notifications
+FORCE_ORANGE_PUBLIC_VAPID_KEY=
+FORCE_ORANGE_PRIVATE_VAPID_KEY=
+
+## Environment
+PORT=8080
+API_URL=http://fo.parisestludique.fr/api