varaverk: replace User Scripts dependency with native job tracking

run_job.sh: new wrapper called by scheduler cron for every job.
  Writes /var/log/varaverk/<id>.json (status/start/end/exit/pid)
  and /var/log/varaverk/<id>.log (latest run output, overwritten).
  Maps exit 0→ok, 1→warn, 2+→error so watchdog "took action" runs
  show warn not error.

scheduler: cron now calls bash run_job.sh instead of inline bash -c.
  Added vv_job_stat_path(). LOG_DIR moved to config.php (shared).

monitor: vv_scripts_status() now reads /var/log/varaverk/*.json and
  */*.json — no User Scripts tmpScripts dependency at all.
  Stale running detection via /proc/<pid> check.
  Returns error_count in addition to running/ok/warn counts.

pages/monitor.php: added error pill (red ✗), error icon/color in
  list, duration shown next to age for each script entry.

Plugin/usr/local/emhttp/plugins/varaverk/include/config.php

@@ -7,6 +7,7 @@ define('PLUGIN_CFG',  '/boot/config/plugins/varaverk/varaverk.cfg');
 $_vv_cfg = @parse_ini_file(PLUGIN_CFG) ?: [];
 define('SCRIPTS_DIR', $_vv_cfg['SCRIPTS_DIR'] ?? '/mnt/user/appdata/unraid_scripts');
 define('CONF_DIR',    SCRIPTS_DIR . '/Configurations');
+define('LOG_DIR',     '/var/log/varaverk');
 unset($_vv_cfg);
 
 function vv_get_hostname(): string {