feat: separate live early-warning + combined score on the regime tab

The event study showed the breadth-divergence signal genuinely leads (warned
before 7/11 drawdowns, ~6 weeks median, where the coincident baseline almost
never did). Surface it live to observe before deciding how to embed it — kept
separate from the index, not folded into its weights.

- regime_monitor daily job now computes breadth-divergence live and attaches a
  separate early_warning score plus a combined blend (weighted mean, default
  0.6/0.4, configurable via combined_weights) to each snapshot, including the
  backfill so the 7/30-day trends populate immediately. Stored in breakdown_json
  — no schema change. Best-effort: a breadth failure can't break the index.
- get_regime_monitor returns the index, early_warning, and combined scores each
  with 7/30-day deltas.
- Regime tab shows three gauges (generalized ScoreGauge): coincident index,
  early warning, and a compact combined blend. Stale snapshots render "—".

Note: the daily regime job now also does a universe-wide breadth scan.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

frontend/src/pages/RegimePage.tsx

@@ -1,4 +1,4 @@
-import { useState } from 'react';
+import { useState, type ReactNode } from 'react';
 import { useQuery, useMutation, useQueryClient } from '@tanstack/react-query';
 import { PageHeader } from '../components/ui/PageHeader';
 import { Callout } from '../components/ui/Callout';
@@ -17,7 +17,6 @@ import {
 } from '../api/regime';
 import type {
   RegimeBand,
-  RegimeMonitor,
   RegimeSignal,
   RegimeConfig,
   RegimeFundamentals,
@@ -49,54 +48,71 @@ function TrendChip({ label, delta }: { label: string; delta: number | null | und
   );
 }
 
-function Gauge({ data }: { data: RegimeMonitor }) {
-  const band = (data.band ?? 'stable') as RegimeBand;
-  const style = BAND_STYLES[band];
-  const score = data.total_score ?? 0;
-  const threshold = data.alert_threshold ?? 65;
+function ScoreGauge({
+  label,
+  score,
+  band,
+  trend,
+  threshold,
+  footnote,
+  size = 'lg',
+}: {
+  label: string;
+  score: number | null | undefined;
+  band: RegimeBand | null | undefined;
+  trend?: { delta_7?: number | null; delta_30?: number | null };
+  threshold?: number;
+  footnote?: ReactNode;
+  size?: 'lg' | 'md';
+}) {
+  const naa = score == null;
+  const style = BAND_STYLES[(band ?? 'stable') as RegimeBand];
+  const s = score ?? 0;
   const clamp = (v: number) => Math.min(100, Math.max(0, v));
+  const numCls = size === 'lg' ? 'text-6xl' : 'text-4xl';
   return (
-    <div className={`glass border ${style.ring} p-6`}>
-      <div className="flex flex-wrap items-end justify-between gap-4">
+    <div className={`glass border ${naa ? 'border-white/[0.06]' : style.ring} p-6`}>
+      <div className="flex flex-wrap items-end justify-between gap-3">
         <div>
-          <div className="flex items-baseline gap-3">
-            <span className={`font-display text-6xl font-bold ${style.text}`}>{Math.round(score)}</span>
-            <span className="text-sm text-gray-500">/ 100</span>
+          <div className="text-[11px] uppercase tracking-wider text-gray-500">{label}</div>
+          <div className="mt-1 flex items-baseline gap-2">
+            <span className={`font-display font-bold ${numCls} ${naa ? 'text-gray-600' : style.text}`}>
+              {naa ? '—' : Math.round(s)}
+            </span>
+            {!naa && <span className="text-sm text-gray-500">/ 100</span>}
           </div>
-          <p className={`mt-1 text-sm font-medium ${style.text}`}>{style.label}</p>
+          {!naa && <p className={`mt-0.5 text-sm font-medium ${style.text}`}>{style.label}</p>}
         </div>
-        <div className="flex flex-wrap gap-2">
-          <TrendChip label="7d" delta={data.trend?.delta_7} />
-          <TrendChip label="30d" delta={data.trend?.delta_30} />
-        </div>
-      </div>
-
-      {/* Band track with score + threshold markers */}
-      <div className="relative mt-6 h-2 w-full rounded-full bg-gradient-to-r from-emerald-500/30 via-amber-500/30 to-red-500/40">
-        <div
-          className="absolute -top-1 h-4 w-0.5 -translate-x-1/2 rounded bg-gray-300/80"
-          style={{ left: `${clamp(threshold)}%` }}
-          title={`Alert threshold ${threshold}`}
-        />
-        <div
-          className={`absolute -top-1.5 h-5 w-5 -translate-x-1/2 rounded-full border-2 border-white/70 ${style.bar}`}
-          style={{ left: `${clamp(score)}%` }}
-        />
-      </div>
-      <div className="mt-1.5 flex justify-between text-[10px] uppercase tracking-wider text-gray-600">
-        <span>0</span><span>30</span><span>60</span><span>80</span><span>100</span>
-      </div>
-
-      <p className="mt-4 text-xs leading-relaxed text-gray-500">
-        An <span className="text-gray-400">index</span> (not a calibrated probability) of how far the AI/Tech bull regime
-        has deteriorated. Mostly coincident signals — it shortens reaction time, it doesn't predict the exact turn.
-        {data.date && <> As of {data.date}.</>}
-        {data.inputs && (data.inputs.vix != null || data.inputs.hy_oas != null) && (
-          <span className="ml-1 text-gray-600">
-            VIX {data.inputs.vix ?? '—'} · HY OAS {data.inputs.hy_oas ?? '—'}
-          </span>
+        {trend && (
+          <div className="flex flex-wrap gap-2">
+            <TrendChip label="7d" delta={trend.delta_7} />
+            <TrendChip label="30d" delta={trend.delta_30} />
+          </div>
         )}
-      </p>
+      </div>
+
+      {!naa && (
+        <>
+          {/* Band track with score (+ optional threshold) markers */}
+          <div className="relative mt-5 h-2 w-full rounded-full bg-gradient-to-r from-emerald-500/30 via-amber-500/30 to-red-500/40">
+            {threshold != null && (
+              <div
+                className="absolute -top-1 h-4 w-0.5 -translate-x-1/2 rounded bg-gray-300/80"
+                style={{ left: `${clamp(threshold)}%` }}
+                title={`Alert threshold ${threshold}`}
+              />
+            )}
+            <div
+              className={`absolute -top-1.5 h-5 w-5 -translate-x-1/2 rounded-full border-2 border-white/70 ${style.bar}`}
+              style={{ left: `${clamp(s)}%` }}
+            />
+          </div>
+          <div className="mt-1.5 flex justify-between text-[10px] uppercase tracking-wider text-gray-600">
+            <span>0</span><span>30</span><span>60</span><span>80</span><span>100</span>
+          </div>
+        </>
+      )}
+      {footnote && <p className="mt-4 text-xs leading-relaxed text-gray-500">{footnote}</p>}
     </div>
   );
 }
@@ -501,7 +517,52 @@ export default function RegimePage() {
 
       {monitor.data && monitor.data.available && (
         <>
-          <Gauge data={monitor.data} />
+          <div className="grid gap-4 lg:grid-cols-2">
+            <ScoreGauge
+              label="Regime index · coincident"
+              score={monitor.data.total_score}
+              band={monitor.data.band}
+              trend={monitor.data.trend}
+              threshold={monitor.data.alert_threshold}
+              footnote={
+                <>
+                  An <span className="text-gray-400">index</span> (not a calibrated probability) of how far the AI/Tech
+                  bull regime has deteriorated. Mostly coincident — it shortens reaction time, it doesn&apos;t predict
+                  the turn.
+                  {monitor.data.date && <> As of {monitor.data.date}.</>}
+                  {monitor.data.inputs && (monitor.data.inputs.vix != null || monitor.data.inputs.hy_oas != null) && (
+                    <span className="ml-1 text-gray-600">
+                      VIX {monitor.data.inputs.vix ?? '—'} · HY OAS {monitor.data.inputs.hy_oas ?? '—'}
+                    </span>
+                  )}
+                </>
+              }
+            />
+            <ScoreGauge
+              label="Early warning · breadth divergence"
+              score={monitor.data.early_warning?.score}
+              band={monitor.data.early_warning?.band}
+              trend={monitor.data.early_warning}
+              footnote={
+                <>
+                  Breadth narrowing while price holds. In the event study it led ~6 weeks on 7/11 past drawdowns, but
+                  it&apos;s noisy (≈2× base rate) and blind to shocks. Observational — separate from the index, not
+                  wired into trades.
+                </>
+              }
+            />
+          </div>
+          <ScoreGauge
+            label="Combined · observational blend"
+            score={monitor.data.combined?.score}
+            band={monitor.data.combined?.band}
+            trend={monitor.data.combined}
+            size="md"
+            footnote={
+              <>A weighted mean of the index and the early warning — for observation only. Tune the mix via the
+              regime config.</>
+            }
+          />
           {monitor.data.breakdown && <Breakdown breakdown={monitor.data.breakdown} />}
         </>
       )}