feat: cockpit command center + skipped trades journal

Dashboard: insert 2 rows of 4 mini-cards between top row and trade ideas
- Row 1: PnL Simulé, Risque Simulé, Dernier Cycle, Régime Macro
- Row 2: Super Contexte, Signaux Géo, Meilleur Pattern, Patterns Actifs
- All cards link to underlying pages via react-router Link

Journal: add 'Non loggés' tab exposing trades suggested by cycle
but skipped because no risk profile was matched
- New skipped_trades table (auto-created on backend restart)
- log_trade_entries() persists each skip with score/gain/asset_class
- GET /api/journal/skipped-trades + useSkippedTrades hook

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/src/hooks/useApi.ts

@@ -472,6 +472,13 @@ export const useTradeCheck = () =>
       api.post('/journal/trade-check', body).then(r => r.data),
   })
 
+export const useSkippedTrades = (days = 30) =>
+  useQuery({
+    queryKey: ['journal-skipped', days],
+    queryFn: () => api.get(`/journal/skipped-trades?days=${days}`).then(r => r.data),
+    staleTime: 60_000,
+  })
+
 // ── Risk Profiles ─────────────────────────────────────────────────────────────
 
 export const useRiskProfiles = () =>