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/shared/components/EmojiOrIcon.vue

@@ -0,0 +1,53 @@
+<script>
+// 🚨 This component is deprecated. Please use fluent-icon instead.
+import { hasEmojiSupport } from 'shared/helpers/emoji';
+import { mapGetters } from 'vuex';
+
+export default {
+  props: {
+    icon: { type: String, default: '' },
+    iconSize: { type: [Number, String], default: 20 },
+    emoji: { type: String, default: '' },
+  },
+  computed: {
+    ...mapGetters({ uiSettings: 'getUISettings' }),
+    isIconTypeEmoji() {
+      const { icon_type: iconType } = this.uiSettings || {};
+      return iconType === 'emoji';
+    },
+    showEmoji() {
+      return this.isIconTypeEmoji && this.emoji && hasEmojiSupport(this.emoji);
+    },
+    showIcon() {
+      return !this.showEmoji && this.icon;
+    },
+    iconContent() {
+      return this.showEmoji ? this.emoji : '';
+    },
+    className() {
+      return {
+        'icon--emoji': this.showEmoji,
+        'icon--font': this.showIcon,
+        [this.icon]: this.showIcon,
+      };
+    },
+  },
+};
+</script>
+
+<template>
+  <i v-if="showEmoji" :class="className">{{ iconContent }}</i>
+  <fluent-icon
+    v-else-if="showIcon"
+    :size="iconSize"
+    :icon="icon"
+    class="flex-shrink-0"
+    :class="className"
+  />
+</template>
+
+<style lang="scss" scoped>
+.icon--emoji {
+  font-style: normal;
+}
+</style>