feat(WARDEN-WP-0021): T1+T2 — scheduled worker tick enabled (systemd --user timer)

T1: systemd --user units (ops-warden-worker.{service,timer}) + scripts/install-worker-timer.sh
(--enable opt-in, cron fallback documented) + examples/worker.env.example. Kill switch:
`systemctl --user disable --now ops-warden-worker.timer` or WORKER_ENABLED=0. Installed and
ENABLED — verified a real systemd run (Result=success, used the llm brain) and the timer is
active (next run +15min).

T2: hardened worker-tick.sh — State Hub /state/health precheck → graceful skip (exit 0) when
unreachable; worker-run failure logged but never fails the unit (retry next tick). Verified
hub-down skip and a live tick.

Conservative tier only; nothing auto-sent. Kill switch is one command.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

examples/worker.env.example

@@ -0,0 +1,15 @@
+# ops-warden scheduled worker config (WARDEN-WP-0021).
+# Installed to ~/.config/warden/worker.env and loaded by the systemd --user service.
+# No secret values belong here.
+
+# State Hub URL the worker reads its inbox from (railiance01 after cust-wp-0011).
+WARDEN_HUB_URL=http://127.0.0.1:8000
+
+# Planner: 'llm' (llm-connect; smarter) or 'rule' (offline, deterministic fallback).
+WORKER_BRAIN=llm
+
+# Master on/off for the tick without touching the timer. 0 = skip every run.
+WORKER_ENABLED=1
+
+# Optional: set a reachable llm-connect URL to skip the per-tick kubectl port-forward.
+# LLM_CONNECT_URL=http://127.0.0.1:18080