feat: add standalone AI/Tech regime-change monitor tab

A new /regime tab scoring how far the AI/Tech bull regime has deteriorated
toward a re-rating as a single 0-100 index with per-signal breakdown and a
7/30-day trend. Intentionally decoupled: nothing reads its output to gate or
score trades — the daily-pipeline membership is scheduling only.

- regime_monitor_service: price sub-scores (P1-P6 via Alpaca, like
  market_regime), VIX + HY credit spreads via a small FRED helper, weighted
  aggregation over available signals (missing source -> n/a, dropped from the
  denominator), one snapshot row/day, and a ~90-day history backfill by
  replaying the already-fetched series as-of each past day.
- F1/F3 fundamentals proposed by the configured grounded LLM (reuses
  sentiment_provider_service config resolution), with a manual override + lock.
- regime_snapshots table (migration 011); endpoints on the existing market
  router; admin-editable weights/threshold; standalone /regime page.

Data needs: prices via Alpaca, VIX/credit via FRED (optional key — signals show
n/a without it). No LLM needed for history.

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

frontend/src/api/regime.ts

@@ -0,0 +1,32 @@
+import apiClient from './client';
+import type { RegimeMonitor, RegimeConfig, RegimeFundamentals } from '../lib/types';
+
+export function getRegimeMonitor() {
+  return apiClient.get<RegimeMonitor>('regime/monitor').then((r) => r.data);
+}
+
+export function getRegimeConfig() {
+  return apiClient.get<RegimeConfig>('regime/config').then((r) => r.data);
+}
+
+export function updateRegimeConfig(updates: Partial<RegimeConfig>) {
+  return apiClient.put<RegimeConfig>('regime/config', updates).then((r) => r.data);
+}
+
+export function getRegimeFundamentals() {
+  return apiClient.get<RegimeFundamentals>('regime/fundamentals').then((r) => r.data);
+}
+
+export function updateRegimeFundamentals(body: {
+  f1_score?: number;
+  f3_score?: number;
+  locked?: boolean;
+}) {
+  return apiClient.put<RegimeFundamentals>('regime/fundamentals', body).then((r) => r.data);
+}
+
+export function refreshRegimeFundamentals() {
+  return apiClient
+    .post<RegimeFundamentals>('regime/fundamentals/refresh')
+    .then((r) => r.data);
+}