Cache the watchdog payload, and stop reading trailing comments as conf values

The tab collected over SSH on every 30s poll — 8.3s a load with HOST2 down.
vv_parse_conf_scalar() captured to end of line, so a commented toggle parsed as
"true   # HOST2 back online": every threshold read right because (int) stops at
the first non-digit, and 38 booleans read wrong. The Fallback tab has been
showing failover disabled while it was on.

Plugin/unraid/Tools/api_cache_writer.php

@@ -147,5 +147,12 @@ vv_cache_write('monitor', $monitor);
 $arrs = vv_arrs_all();
 vv_cache_write('arrs', $arrs);
 
+// ── Watchdog payload ──────────────────────────────────────────────────────────
+// Here for the same reason as the other two: vv_wd_all() SSHes to every partner, which cost 8.3s
+// on this host with HOST2 down, and the Watchdog tab polls every 30 seconds. Collected off the
+// request path it is paid once a minute by cron instead of by whoever has the tab open.
+require_once $_base . '/include/watchdog.php';
+vv_cache_write('watchdog', vv_wd_all());
+
 $elapsed = round((microtime(true) - $t) * 1000);
-echo "Cache written in {$elapsed}ms — monitor + arrs\n";
+echo "Cache written in {$elapsed}ms — monitor + arrs + watchdog\n";