fix(contribuyente-selector): limpiar selección inválida de localStorage

apps/web/components/contribuyente-selector.tsx

@@ -33,6 +33,16 @@ export function ContribuyenteSelector() {
     }
   }, [contribuyentes, selectedContribuyenteId, setSelectedContribuyente]);
 
+  // Clear invalid selection (e.g. stale localStorage from another tenant/session)
+  useEffect(() => {
+    if (contribuyentes && contribuyentes.length > 0 && selectedContribuyenteId) {
+      const exists = contribuyentes.some(c => c.id === selectedContribuyenteId);
+      if (!exists) {
+        clearSelectedContribuyente();
+      }
+    }
+  }, [contribuyentes, selectedContribuyenteId, clearSelectedContribuyente]);
+
   if (isLoading || !contribuyentes || contribuyentes.length === 0) return null;
   if (pathname && HIDDEN_PATHS.some(p => pathname === p || pathname.startsWith(`${p}/`))) return null;