feat: company names for tickers (Alpaca backfill + subtle display)

Store an optional company name on Ticker (migration 014) and backfill it from
Alpaca's asset list in a single Trading-API call for the whole universe — no
per-ticker fetch. Runs automatically at the end of universe bootstrap and via a
manual "Backfill Names" button (admin) / POST /admin/tickers/backfill-names.

The name ships on /tickers; a shared symbol→name map (useTickerNames) lets any view
show it without its own request. Displayed subtly next to the symbol — in the global
search, the ticker header, and as a small muted line under the symbol in Top Setups
and Open Trades (no extra column, truncated so it never widens the table).

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

frontend/src/components/admin/TickerUniverseBootstrap.tsx

@@ -1,5 +1,6 @@
 import { useEffect, useState } from 'react';
 import {
+  useBackfillTickerNames,
   useBootstrapTickers,
   useTickerUniverseSetting,
   useUpdateTickerUniverseSetting,
@@ -17,6 +18,7 @@ export function TickerUniverseBootstrap() {
   const { data, isLoading, isError, error } = useTickerUniverseSetting();
   const updateDefault = useUpdateTickerUniverseSetting();
   const bootstrap = useBootstrapTickers();
+  const backfillNames = useBackfillTickerNames();
 
   const [universe, setUniverse] = useState<TickerUniverse>('sp500');
   const [pruneMissing, setPruneMissing] = useState(false);
@@ -85,6 +87,14 @@ export function TickerUniverseBootstrap() {
         >
           {bootstrap.isPending ? 'Bootstrapping…' : 'Bootstrap Now'}
         </button>
+        <button
+          className="px-4 py-2 text-sm rounded border border-white/[0.1] text-gray-300 hover:text-white disabled:opacity-50"
+          onClick={() => backfillNames.mutate()}
+          disabled={backfillNames.isPending}
+          title="Fill in company names from Alpaca (one request for all tickers)"
+        >
+          {backfillNames.isPending ? 'Backfilling…' : 'Backfill Names'}
+        </button>
       </div>
     </div>
   );