feat(scheduler+ntp): Memory-Alerts + NTP-Status freq/rms — v1.1.107

- Scheduler: runMemoryCheck() liest /proc/meminfo, feuert Warning bei ≥85% und Critical bei ≥95% RAM-Auslastung (5-Min-Intervall, 1h dedupe pro Severity-Key)
- NTP-Status-Karte: freq_ppm (±ppm mit Warnung bei >100) und rms_offset_ms werden jetzt angezeigt — Felder waren im Backend schon vorhanden, aber nie gerendert
- Alerts scopeDesc: mem.high-Trigger in beiden i18n-Dateien dokumentiert

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

management-ui/src/i18n/locales/de/common.json

@@ -837,6 +837,9 @@
       "stratum": "Stratum",
       "offset": "Offset",
       "offsetHint": "Zeitdifferenz zur Referenzquelle. Werte > 100 ms sind ungewöhnlich — Netzwerkprobleme oder fehlkonfigurierte Quelle prüfen.",
+      "freqPpm": "Frequenzfehler",
+      "freqPpmHint": "Frequenzabweichung der lokalen Uhr zur Referenz. Werte > ±100 ppm weisen auf eine driftende Uhr oder einen Hardware-Defekt hin.",
+      "rmsOffset": "RMS-Offset",
       "loading": "Lade…"
     },
     "pool": {
@@ -1116,7 +1119,7 @@
     "title": "Health-Alarme",
     "intro": "Notification-Channels für kritische Events. Webhook (Slack/Discord/Teams/Generic-HTTP) oder Email (SMTP). Triggers: cert.expiring (<14 d), cert.renew_failed, backup.failed, license.invalid.",
     "scopeTitle": "Was triggert Alarme?",
-    "scopeDesc": "cert.expiring — TLS-Zertifikat <14 Tage Restzeit (dedupe 12h). cert.renew_failed — ACME-Renewer hat Fails. backup.failed — Scheduled Backup konnte nicht erstellt werden. license.invalid — License-Server liefert valid=false. backend.down — alle Server eines Backend-Pools sind DOWN (2-Min-Check, dedupe 12h). disk.full — Root-Filesystem ≥80% Warnung, ≥90% Critical (stündlich, dedupe 12h).",
+    "scopeDesc": "cert.expiring — TLS-Zertifikat <14 Tage Restzeit (dedupe 12h). cert.renew_failed — ACME-Renewer hat Fails. backup.failed — Scheduled Backup konnte nicht erstellt werden. license.invalid — License-Server liefert valid=false. backend.down — alle Server eines Backend-Pools sind DOWN (2-Min-Check, dedupe 12h). disk.full — Root-Filesystem ≥80% Warnung, ≥90% Critical (stündlich, dedupe 12h). mem.high — RAM-Auslastung ≥85% Warnung, ≥95% Critical (5-Min-Check, dedupe 1h).",
     "tabs": { "channels": "Channels", "events": "History" },
     "add": "Channel hinzufügen",
     "addTitle": "Notification-Channel anlegen",

management-ui/src/i18n/locales/en/common.json

@@ -837,6 +837,9 @@
       "stratum": "Stratum",
       "offset": "Offset",
       "offsetHint": "Time difference to reference source. Values > 100 ms are unusual — check network or misconfigured source.",
+      "freqPpm": "Freq. error",
+      "freqPpmHint": "Frequency error of the local clock vs. reference. Values > ±100 ppm indicate a drifting clock or hardware issue.",
+      "rmsOffset": "RMS offset",
       "loading": "Loading…"
     },
     "pool": {
@@ -1116,7 +1119,7 @@
     "title": "Health alerts",
     "intro": "Notification channels for critical events. Webhook (Slack/Discord/Teams/generic-HTTP) or email (SMTP). Triggers: cert.expiring (<14 d), cert.renew_failed, backup.failed, license.invalid.",
     "scopeTitle": "What triggers alerts?",
-    "scopeDesc": "cert.expiring — TLS cert <14 days remaining (12 h dedupe). cert.renew_failed — ACME renewer cycle had failures. backup.failed — scheduled backup couldn't run. license.invalid — License server returns valid=false. backend.down — all servers in a backend pool are DOWN (2 min check, 12 h dedupe). disk.full — root filesystem ≥80% warning, ≥90% critical (hourly check, 12 h dedupe).",
+    "scopeDesc": "cert.expiring — TLS cert <14 days remaining (12 h dedupe). cert.renew_failed — ACME renewer cycle had failures. backup.failed — scheduled backup couldn't run. license.invalid — License server returns valid=false. backend.down — all servers in a backend pool are DOWN (2 min check, 12 h dedupe). disk.full — root filesystem ≥80% warning, ≥90% critical (hourly check, 12 h dedupe). mem.high — RAM usage ≥85% warning, ≥95% critical (5 min check, 1 h dedupe).",
     "tabs": { "channels": "Channels", "events": "History" },
     "add": "Add channel",
     "addTitle": "Add notification channel",

management-ui/src/pages/NTP/index.tsx

@@ -161,6 +161,29 @@ export default function NTPPage() {
                 />
               </Tooltip>
             </Col>
+            {ntpStatus.freq_ppm != null && (
+              <Col xs={12} sm={6}>
+                <Tooltip title={t('ntp.statusCard.freqPpmHint')}>
+                  <Statistic
+                    title={t('ntp.statusCard.freqPpm')}
+                    value={(ntpStatus.freq_ppm >= 0 ? '+' : '') + ntpStatus.freq_ppm.toFixed(3) + ' ppm'}
+                    valueStyle={{
+                      fontSize: 13,
+                      color: Math.abs(ntpStatus.freq_ppm) > 100 ? '#d48806' : undefined,
+                    }}
+                  />
+                </Tooltip>
+              </Col>
+            )}
+            {ntpStatus.rms_offset_ms != null && ntpStatus.rms_offset_ms > 0 && (
+              <Col xs={12} sm={6}>
+                <Statistic
+                  title={t('ntp.statusCard.rmsOffset')}
+                  value={ntpStatus.rms_offset_ms.toFixed(3) + ' ms'}
+                  valueStyle={{ fontSize: 13 }}
+                />
+              </Col>
+            )}
           </Row>
         ) : (
           <Typography.Text type="secondary">{t('ntp.statusCard.loading')}</Typography.Text>