fix: QA remediation P1-D + P2 for infra/vps orchestrator (v1.8.0)

P1-D: bump package.json version 1.7.2 → 1.8.0 and add [1.8.0] CHANGELOG
entry documenting the infra/vps/ PRAB generation orchestrator addition.

P2 (security): replace StrictHostKeyChecking=no with StrictHostKeyChecking=accept-new
in all three SSH invocations in orchestrate-generation.sh. Add
UserKnownHostsFile=${KNOWN_HOSTS} (-o) to pin key verification to the
pre-seeded file rather than the root known_hosts.

install-orchestrator.sh: add ssh-keyscan step that pre-populates
/opt/prab-orchestrator/known_hosts with Hostinger's host key on first
install. Graceful degradation: if ssh-keyscan fails, logs WARN and
proceeds (accept-new will add the key on first real connect).

prab-generation.service: add justifying comment for User=root (root holds
the Hostinger SSH key + known_hosts in /root/.ssh/ and /opt/prab-orchestrator/).

Agent-Session: prab-reliability-remediation-20260622

CHANGELOG.md

@@ -1,5 +1,22 @@
 # Changelog
 
+## [1.8.0] - 2026-06-23
+
+### Added
+- **`infra/vps/` PRAB generation orchestrator**: systemd timer + service + bash
+  script that SSHes from the Coolify KVM8 VPS to Hostinger and drives
+  `wp prautoblogger generate --sync` in a held-open SSH session. Sidesteps
+  Hostinger's ~10-min background-PHP-process kill that was blocking full
+  generation runs. Components:
+  - `orchestrate-generation.sh`: main script with DRY_RUN mode, structured
+    logging, reaper pre-sweep, failure email alert, and shellcheck-clean quoting.
+  - `prab-generation.service` / `prab-generation.timer`: systemd oneshot service
+    (2h timeout, no auto-restart) + daily 06:00 UTC timer with 5-min jitter.
+  - `install-orchestrator.sh`: one-time setup script; installs units but does NOT
+    enable the timer (requires explicit CEO greenlight post-QA).
+  - Security: `StrictHostKeyChecking=accept-new` with pre-seeded known_hosts for
+    the Hostinger IP; no hardcoded secrets; SSH key referenced by env-var path.
+
 ## [1.7.2] - 2026-06-17
 
 ### Fixed