V2.0.1: listen override fix, sing-box core fetch, probe settings page + fast report, spx removal, core mem env

- 0: sing-box gen overrides fragment listen/port from the inbound row
  (empty listen -> "::"), Update/Add recompute the stored fragment;
  non-loopback E2E against the real core binary.
- 1: agent fetches the sing-box core from the Gitea release when
  missing, self-checks it, and only then latches the switch.
- 2: node list shows the sing-box core version (heartbeat field,
  persisted on the node row), xray version as fallback.
- 3: public-page fallback returns 404 to anonymous visitors when the
  page is disabled.
- 4: settings restart hint bar removed, dead i18n keys cleaned.
- 5: two PUT calls missing JSON headers fixed (audit: only those two),
  batch probe-task creation endpoint + UI.
- 6: cf-probe retirement card and coverage pipeline removed.
- 7: generated vless links no longer carry spx (panel export + sub);
  parser still accepts spx; golden fixtures updated.
- probe batch: dedicated probe settings tab (public-page settings,
  tasks, per-node meta), retention_days editable, per-node traffic
  calibration + stat-interface pinning, runtime metrics split into a
  lightweight fast report (default 3s, 1-60s adjustable).
- 8: sing-box core processes start with GOMEMLIMIT=32MiB, GOGC=50.
- 9: dead /getTwoFactorEnable docs entries removed (frontend call and
  contract entry already gone at base; verified by grep).

frontend/src/pages/nodes/ProbeMetaSection.tsx

@@ -23,8 +23,15 @@ interface ProbeMetaWire {
   countryPin: string;
   ipv4Pin: string;
   ipv6Pin: string;
+  // V2.0.1: ledger corrections in GB (either sign) and the counted
+  // interface pin ('' = automatic selection on the agent).
+  trafficCalUpGb: number;
+  trafficCalDownGb: number;
+  statIface: string;
 }
 
+const JSON_HEADERS = { headers: { 'Content-Type': 'application/json' } };
+
 const NAMED_CYCLES = [
   'once',
   'monthly',
@@ -113,6 +120,7 @@ export default function ProbeMetaSection({ nodeId }: { nodeId: number }) {
       };
       const msg = await HttpUtil.put(`/panel/api/agent/probe-meta/${nodeId}`, payload, {
         silent: true,
+        ...JSON_HEADERS,
       });
       if (msg?.success) {
         setLoaded({ nodeId, meta: payload });
@@ -237,6 +245,38 @@ export default function ProbeMetaSection({ nodeId }: { nodeId: number }) {
           </Field>
         </Col>
       </Row>
+      <Row gutter={16}>
+        <Col xs={24} md={8}>
+          <Field label={t('pages.nodes.probe.calUp')}>
+            <InputNumber
+              value={meta.trafficCalUpGb}
+              step={0.1}
+              onChange={(v) => set('trafficCalUpGb', v ?? 0)}
+              style={{ width: '100%' }}
+            />
+          </Field>
+        </Col>
+        <Col xs={24} md={8}>
+          <Field label={t('pages.nodes.probe.calDown')}>
+            <InputNumber
+              value={meta.trafficCalDownGb}
+              step={0.1}
+              onChange={(v) => set('trafficCalDownGb', v ?? 0)}
+              style={{ width: '100%' }}
+            />
+          </Field>
+        </Col>
+        <Col xs={24} md={8}>
+          <Field label={t('pages.nodes.probe.statIface')}>
+            <Input
+              value={meta.statIface}
+              placeholder="eth0"
+              onChange={(e) => set('statIface', e.target.value)}
+            />
+          </Field>
+        </Col>
+      </Row>
+      <p style={{ marginTop: -4, marginBottom: 12 }}>{t('pages.nodes.probe.calHint')}</p>
       <Row gutter={16}>
         <Col xs={24} md={8}>
           <Field label={t('pages.nodes.probe.countryPin')}>