feat: Sistema de gestión de impresoras persistente

- Crear modelo Printer con campos: id, name, host, deviceId, timeout, isDefault
- Almacenamiento persistente en data/printers.json
- APIs CRUD: GET/POST /api/printers, GET/PUT/DELETE /api/printers/:id
- API para seleccionar impresora activa: POST /api/printers/select
- Endpoint de impresión ahora usa la impresora seleccionada o la especificada por printerId
- Composable usePrinters() para el cliente
- UI: Selector de impresora en sidebar, tab Impresoras en mobile
- Componentes: PrintersList, PrintersCard, PrintersForm, PrintersSelector

app/components/printers/Form.vue

@@ -0,0 +1,114 @@
+<script setup lang="ts">
+import type { Printer } from '~/composables/usePrinters'
+
+const props = defineProps<{
+  printer?: Printer | null
+}>()
+
+const emit = defineEmits<{
+  submit: [data: {
+    name: string
+    host: string
+    deviceId: string
+    timeout: number
+    isDefault: boolean
+  }]
+  cancel: []
+}>()
+
+const form = reactive({
+  name: props.printer?.name || '',
+  host: props.printer?.host || '',
+  deviceId: props.printer?.deviceId || '',
+  timeout: props.printer?.timeout || 60000,
+  isDefault: props.printer?.isDefault || false
+})
+
+// Actualizar form cuando cambia el printer
+watch(() => props.printer, (newPrinter) => {
+  if (newPrinter) {
+    form.name = newPrinter.name
+    form.host = newPrinter.host
+    form.deviceId = newPrinter.deviceId
+    form.timeout = newPrinter.timeout
+    form.isDefault = newPrinter.isDefault
+  } else {
+    form.name = ''
+    form.host = ''
+    form.deviceId = ''
+    form.timeout = 60000
+    form.isDefault = false
+  }
+})
+
+function handleSubmit() {
+  if (!form.name || !form.host || !form.deviceId) return
+
+  emit('submit', {
+    name: form.name,
+    host: form.host,
+    deviceId: form.deviceId,
+    timeout: form.timeout,
+    isDefault: form.isDefault
+  })
+}
+</script>
+
+<template>
+  <form class="space-y-4" @submit.prevent="handleSubmit">
+    <UFormField label="Nombre" required>
+      <UInput
+        v-model="form.name"
+        placeholder="Ej: Impresora Cocina"
+        class="w-full"
+      />
+    </UFormField>
+
+    <UFormField label="Host / IP" required>
+      <UInput
+        v-model="form.host"
+        placeholder="Ej: 192.168.1.100"
+        class="w-full"
+      />
+    </UFormField>
+
+    <UFormField label="Device ID" required>
+      <UInput
+        v-model="form.deviceId"
+        placeholder="Ej: local_printer"
+        class="w-full"
+      />
+    </UFormField>
+
+    <UFormField label="Timeout (ms)">
+      <UInput
+        v-model.number="form.timeout"
+        type="number"
+        placeholder="60000"
+        class="w-full"
+      />
+    </UFormField>
+
+    <UCheckbox
+      v-model="form.isDefault"
+      label="Establecer como impresora predeterminada"
+    />
+
+    <div class="flex justify-end gap-2 pt-4">
+      <UButton
+        type="button"
+        color="neutral"
+        variant="ghost"
+        @click="emit('cancel')"
+      >
+        Cancelar
+      </UButton>
+      <UButton
+        type="submit"
+        :disabled="!form.name || !form.host || !form.deviceId"
+      >
+        {{ printer ? 'Guardar cambios' : 'Agregar impresora' }}
+      </UButton>
+    </div>
+  </form>
+</template>