Vendor Chatwoot Vue 3 frontend into frontend/

Copy the Chatwoot (v4.14.0) frontend runnable subset into frontend/ for
customization:
- app/javascript/ (Vue SPA: dashboard, widget, sdk, portal, superadmin)
- app/views/ (ERB templates for vite-plugin-ruby entrypoint resolution)
- app/helpers/, app/assets/ (Rails view helpers, static assets)
- enterprise/ (Enterprise edition frontend overlay)
- config/vite.json, vite.config.ts, bin/vite (Vite-Rails toolchain)
- package.json, pnpm-lock.yaml, tailwind/postcss/eslint configs
- Gemfile, Gemfile.lock (vite_rails gem for bin/vite binstub)

Excluded Rails backend: controllers, models, services, jobs, mailers,
policies, db, lib, spec, public, node_modules.

Update references to the new frontend location:
- .gitignore: exclude frontend build artifacts (node_modules, tmp, packs),
  keep frontend/bin/ and frontend/vendor/ via negation
- backend/scripts/parity_frontend_smoke.sh: CHATWOOT_DIR default
  reference/chatwoot -> ../frontend
- backend/scripts/parity_frontend_browser_smoke.mjs: same default update
- AGENTS.md: add frontend section with Rails/Vite coupling notes
- README: architecture tree includes frontend/

frontend/app/javascript/dashboard/components-next/Contacts/EmptyState/ContactEmptyState.vue

@@ -0,0 +1,66 @@
+<script setup>
+import { ref } from 'vue';
+
+import EmptyStateLayout from 'dashboard/components-next/EmptyStateLayout.vue';
+import CreateNewContactDialog from 'dashboard/components-next/Contacts/ContactsForm/CreateNewContactDialog.vue';
+import Button from 'dashboard/components-next/button/Button.vue';
+import ContactsCard from 'dashboard/components-next/Contacts/ContactsCard/ContactsCard.vue';
+import contactContent from 'dashboard/components-next/Contacts/EmptyState/contactEmptyStateContent';
+
+defineProps({
+  title: {
+    type: String,
+    default: '',
+  },
+  subtitle: {
+    type: String,
+    default: '',
+  },
+  showButton: {
+    type: Boolean,
+    default: true,
+  },
+  buttonLabel: {
+    type: String,
+    default: '',
+  },
+});
+
+const emit = defineEmits(['create']);
+
+const createNewContactDialogRef = ref(null);
+
+const onClick = () => {
+  createNewContactDialogRef.value?.dialogRef.open();
+};
+</script>
+
+<template>
+  <EmptyStateLayout :title="title" :subtitle="subtitle">
+    <template #empty-state-item>
+      <div class="grid grid-cols-1 gap-4 p-px overflow-hidden">
+        <ContactsCard
+          v-for="contact in contactContent.slice(0, 5)"
+          :id="contact.id"
+          :key="contact.id"
+          :name="contact.name"
+          :email="contact.email"
+          :thumbnail="contact.thumbnail"
+          :phone-number="contact.phoneNumber"
+          :additional-attributes="contact.additionalAttributes"
+          :is-expanded="0 === contact.id"
+          @toggle="toggleExpanded(contact.id)"
+        />
+      </div>
+    </template>
+    <template #actions>
+      <div v-if="showButton">
+        <Button :label="buttonLabel" icon="i-lucide-plus" @click="onClick" />
+        <CreateNewContactDialog
+          ref="createNewContactDialogRef"
+          @create="emit('create', $event)"
+        />
+      </div>
+    </template>
+  </EmptyStateLayout>
+</template>