feat(workers): systemd unit + push-workers.sh

Deploy README extended with workers bootstrap + note on the void2-db
SQL_ASCII cluster requiring client_encoding=UTF8 on Python clients.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

deploy/void-workers.service

@@ -0,0 +1,19 @@
+[Unit]
+Description=Void 2.0 workers
+After=network-online.target void-server.service
+Wants=network-online.target
+
+[Service]
+Type=simple
+User=voidworkers
+WorkingDirectory=/opt/void-workers
+EnvironmentFile=/opt/void-workers/.env
+ExecStart=/opt/void-workers/venv/bin/python -m void_workers.runner
+Restart=on-failure
+RestartSec=5
+StandardOutput=journal
+StandardError=journal
+MemoryMax=6G
+
+[Install]
+WantedBy=multi-user.target