fix: fetch trend history per-window and run aggregation 24/7

Two fixes for missing intraday data:

1. Frontend: lifted selectedWindow state to page level so useTrendHistory
   passes window param to the API. Previously fetched all windows with
   limit=500 which exhausted the limit before reaching recent intraday
   data. Now fetches only the selected window's data.

2. Scheduler: removed market-hours-only restriction from periodic
   aggregation. Runs every 15 minutes 24/7 so intraday data is always
   populated for backtesting regardless of market state.

frontend/src/pages/CompanyDetail.tsx

@@ -44,7 +44,8 @@ export function CompanyDetailPage() {
   const { data: signals } = useCompetitiveSignals(company?.ticker);
   const { data: decisions } = useCorporateDecisions(company?.ticker);
   const { data: trends } = useTrends({ ticker: company?.ticker, limit: 200 });
-  const { data: trendHistory } = useTrendHistory({ ticker: company?.ticker, limit: 500 });
+  const [selectedWindow, setSelectedWindow] = useState('7d');
+  const { data: trendHistory } = useTrendHistory({ ticker: company?.ticker, window: selectedWindow, limit: 500 });
   const { data: marketPrices } = useMarketPrices(company?.ticker, 200);
   const { data: positions } = usePositions(company?.ticker);
   const [tab, setTab] = useState<'trends' | 'sources' | 'aliases' | 'macro' | 'competitors' | 'patterns' | 'signals' | 'decisions'>('trends');
@@ -87,7 +88,7 @@ export function CompanyDetailPage() {
       {tab === 'trends' && (
         <div className="space-y-4">
           <PositionCard positions={positions ?? []} ticker={company.ticker} />
-          <TrendHistoryChart trends={trendHistory ?? []} latestTrends={trends ?? []} ticker={company.ticker} marketPrices={marketPrices ?? []} />
+          <TrendHistoryChart trends={trendHistory ?? []} latestTrends={trends ?? []} ticker={company.ticker} marketPrices={marketPrices ?? []} selectedWindow={selectedWindow} onWindowChange={setSelectedWindow} />
         </div>
       )}
 
@@ -662,8 +663,7 @@ function PositionCard({ positions, ticker }: { positions: import('../api/hooks')
   );
 }
 
-function TrendHistoryChart({ trends, latestTrends, ticker, marketPrices }: { trends: TrendSummary[]; latestTrends: TrendSummary[]; ticker: string; marketPrices: MarketPrice[] }) {
-  const [selectedWindow, setSelectedWindow] = useState('7d');
+function TrendHistoryChart({ trends, latestTrends, ticker, marketPrices, selectedWindow, onWindowChange }: { trends: TrendSummary[]; latestTrends: TrendSummary[]; ticker: string; marketPrices: MarketPrice[]; selectedWindow: string; onWindowChange: (w: string) => void }) {
 
   // Determine the time range for the selected window to filter data
   const windowHours: Record<string, number> = {
@@ -742,7 +742,7 @@ function TrendHistoryChart({ trends, latestTrends, ticker, marketPrices }: { tre
         {(availableWindows.length > 0 ? availableWindows : WINDOW_ORDER).map((w) => (
           <button
             key={w}
-            onClick={() => setSelectedWindow(w)}
+            onClick={() => onWindowChange(w)}
             className={`rounded-md px-3 py-1 text-xs font-medium transition-colors ${
               selectedWindow === w
                 ? 'bg-brand-600 text-white'