fix: configure asciinema SMTP with EMAIL_FROM and disable signup

- Add EMAIL_FROM to arty.yml environment defaults
- Configure asciinema to use EMAIL_FROM for MAIL_FROM_ADDRESS
- Set SMTP_SSL to true for IONOS SMTP on port 465
- Set SIGN_UP_DISABLED default to false (will enable after admin creation)
- Follow netdata compose.yaml pattern for Traefik labels
- Add proper HTTP to HTTPS redirect middlewares
- Configure compression and security headers

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

arty.yml

@@ -10,6 +10,7 @@ envs:
     ADMIN_EMAIL: valknar@pivoine.art
     NETWORK_NAME: falcon_network
     TIMEZONE: Europe/Berlin
+    EMAIL_FROM: hi@pivoine.art
     # Core
     CORE_COMPOSE_PROJECT_NAME: core
     CORE_DB_HOST: postgres
@@ -186,8 +187,8 @@ envs:
     ASCIINEMA_IMAGE: ghcr.io/asciinema/asciinema-server:latest
     ASCIINEMA_TRAEFIK_HOST: asciinema.pivoine.art
     ASCIINEMA_DB_NAME: asciinema
+    ASCIINEMA_SIGN_UP_DISABLED: false
     ASCIINEMA_UNCLAIMED_TTL: 30
-    ASCIINEMA_MAIL_FROM: noreply@pivoine.art
     ASCIINEMA_MAIL_REPLY_TO: valknar@pivoine.art
     # Watchtower
     WATCHTOWER_POLL_INTERVAL: 300