feat: agrega km y chasis al turno/auto, combobox de marcas y modelos

- Turno.kilometros (requerido al reservar)
- Auto.nroChasis (opcional)
- Combobox con 60 marcas mundiales y modelos precargados
- Modelo se habilita al seleccionar marca

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

src/app/cliente/dashboard/page.tsx

@@ -5,6 +5,8 @@ import Link from "next/link";
 import Button from "@/components/ui/Button";
 import Card from "@/components/ui/Card";
 import Input from "@/components/ui/Input";
+import Combobox from "@/components/ui/Combobox";
+import { MARCAS, getModelos } from "@/lib/marcas-modelos";
 
 interface Auto {
   id: string;
@@ -12,6 +14,7 @@ interface Auto {
   marca: string;
   modelo: string;
   anio: number;
+  nroChasis?: string | null;
 }
 
 export default function DashboardPage() {
@@ -19,7 +22,8 @@ export default function DashboardPage() {
   const [autos, setAutos] = useState<Auto[]>([]);
   const [loading, setLoading] = useState(true);
   const [mostrarForm, setMostrarForm] = useState(false);
-  const [form, setForm] = useState({ patente: "", marca: "", modelo: "", anio: "" });
+  const [form, setForm] = useState({ patente: "", marca: "", modelo: "", anio: "", nroChasis: "" });
+  const modelosDisponibles = getModelos(form.marca);
   const [guardando, setGuardando] = useState(false);
   const [errorForm, setErrorForm] = useState("");
 
@@ -51,7 +55,7 @@ export default function DashboardPage() {
     setGuardando(false);
     if (!res.ok) { setErrorForm(data.error || "Error al guardar"); return; }
     setMostrarForm(false);
-    setForm({ patente: "", marca: "", modelo: "", anio: "" });
+    setForm({ patente: "", marca: "", modelo: "", anio: "", nroChasis: "" });
     cargarAutos();
   }
 
@@ -108,10 +112,30 @@ export default function DashboardPage() {
         <Card title="Agregar auto">
           <form onSubmit={agregarAuto} className="flex flex-col gap-4">
             <div className="grid grid-cols-2 gap-4">
-              <Input id="marca" label="Marca" placeholder="Ford" value={form.marca} onChange={set("marca")} required />
-              <Input id="modelo" label="Modelo" placeholder="Focus" value={form.modelo} onChange={set("modelo")} required />
+              <Combobox
+                id="marca"
+                label="Marca"
+                options={MARCAS}
+                value={form.marca}
+                onChange={(v) => setForm((f) => ({ ...f, marca: v, modelo: "" }))}
+                onSelect={(v) => setForm((f) => ({ ...f, marca: v, modelo: "" }))}
+                placeholder="Ford"
+                required
+              />
+              <Combobox
+                id="modelo"
+                label="Modelo"
+                options={modelosDisponibles}
+                value={form.modelo}
+                onChange={(v) => setForm((f) => ({ ...f, modelo: v }))}
+                onSelect={(v) => setForm((f) => ({ ...f, modelo: v }))}
+                placeholder={form.marca ? "Focus" : "Primero elegí la marca"}
+                disabled={modelosDisponibles.length === 0}
+                required
+              />
               <Input id="anio" label="Año" type="number" placeholder="2018" value={form.anio} onChange={set("anio")} required min={1960} max={new Date().getFullYear() + 1} />
               <Input id="patente" label="Patente" placeholder="AB123CD" value={form.patente} onChange={set("patente")} required className="uppercase" />
+              <Input id="nroChasis" label="Nº Chasis (opcional)" placeholder="8AFZZZ11ZYM569874" value={form.nroChasis} onChange={set("nroChasis")} className="col-span-2" />
             </div>
             {errorForm && <p className="text-sm text-red-500">{errorForm}</p>}
             <div className="flex gap-2 justify-end">