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/hooks/useAdmin.ts

@@ -283,6 +283,22 @@ export function useBootstrapTickers() {
   });
 }
 
+export function useBackfillTickerNames() {
+  const qc = useQueryClient();
+  const { addToast } = useToast();
+
+  return useMutation({
+    mutationFn: () => adminApi.backfillTickerNames(),
+    onSuccess: (result) => {
+      qc.invalidateQueries({ queryKey: ['tickers'] });
+      addToast('success', `Company names: +${result.updated} filled (${result.unmatched} unmatched)`);
+    },
+    onError: (error: Error) => {
+      addToast('error', error.message || 'Failed to backfill company names');
+    },
+  });
+}
+
 // ── Jobs ──
 
 export function useJobs() {

frontend/src/hooks/useTickers.ts

@@ -1,3 +1,4 @@
+import { useMemo } from 'react';
 import { useMutation, useQuery, useQueryClient } from '@tanstack/react-query';
 import * as tickersApi from '../api/tickers';
 import { useToast } from '../components/ui/Toast';
@@ -9,6 +10,19 @@ export function useTickers() {
   });
 }
 
+/** symbol (upper) → company name, from the tracked-ticker list. Shared lookup so
+ *  any view can show the company behind a symbol without its own request. */
+export function useTickerNames(): Map<string, string> {
+  const { data } = useTickers();
+  return useMemo(() => {
+    const map = new Map<string, string>();
+    for (const t of data ?? []) {
+      if (t.name) map.set(t.symbol.toUpperCase(), t.name);
+    }
+    return map;
+  }, [data]);
+}
+
 export function useAddTicker() {
   const qc = useQueryClient();
   const { addToast } = useToast();