feat: run dream cycle as a systemd user service + journald-visible logs

- deploy/lyra-dream.service: --loop 1800 user service on lyra-cortex, so Lyra's
  consolidation + reflection keeps ticking unattended between conversations
- deploy/README.md: install / linger / operate runbook
- logbus: mirror events to stderr so out-of-band runs (the dream service under
  journald) are observable, not just via the in-process web SSE feed

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

deploy/lyra-dream.service

@@ -0,0 +1,15 @@
+[Unit]
+Description=Lyra dream cycle — unattended consolidation + reflection loop
+Documentation=https://github.com/serversdown/project-lyra
+
+[Service]
+Type=simple
+WorkingDirectory=/home/serversdown/project-lyra
+# Clear any stray VIRTUAL_ENV so uv resolves the project's own .venv.
+UnsetEnvironment=VIRTUAL_ENV
+ExecStart=/home/serversdown/.local/bin/uv run lyra-dream --loop 1800
+Restart=on-failure
+RestartSec=30
+
+[Install]
+WantedBy=default.target