Restructure omni services and add Chatwoot research snapshot

research/chatwoot/app/javascript/shared/composables/useLocale.js

@@ -0,0 +1,57 @@
+import { computed } from 'vue';
+import { useI18n } from 'vue-i18n';
+
+/**
+ * Composable for locale resolution and validation
+ * Provides a normalized, validated locale that works with Intl APIs
+ */
+export function useLocale() {
+  const { locale } = useI18n();
+
+  /**
+   * Resolves and validates the current locale for use with Intl APIs
+   *
+   * Handles multiple fallback scenarios:
+   * 1. Normalizes underscore-based tags (pt_BR → pt-BR, zh_CN → zh-CN)
+   * 2. Falls back to base language if specific locale unsupported (pt-BR → pt)
+   * 3. Falls back to English if base language unsupported (xx-YY → en)
+   *
+   * @returns {string} Valid BCP 47 locale tag for Intl APIs
+   *
+   * @example
+   * const { resolvedLocale } = useLocale();
+   * new Intl.NumberFormat(resolvedLocale.value).format(1234);
+   * new Intl.DateTimeFormat(resolvedLocale.value).format(new Date());
+   */
+  const resolvedLocale = computed(() => {
+    // Handle null/undefined locale
+    if (!locale.value) return 'en';
+
+    // Normalize underscore to hyphen (pt_BR → pt-BR, zh_CN → zh-CN)
+    const normalized = locale.value.replace(/_/g, '-');
+
+    // Check if the specific locale is supported (e.g., pt-BR, zh-CN)
+    const supportedLocales = Intl.NumberFormat.supportedLocalesOf([normalized]);
+    if (supportedLocales.length > 0) {
+      return normalized;
+    }
+
+    // If specific locale not supported, try base language (pt-BR → pt, zh-CN → zh)
+    const baseLocale = normalized.split('-')[0];
+    const baseSupportedLocales = Intl.NumberFormat.supportedLocalesOf([
+      baseLocale,
+    ]);
+    if (baseSupportedLocales.length > 0) {
+      return baseLocale;
+    }
+
+    // If base language also not supported, fall back to English
+    return 'en';
+  });
+
+  return {
+    resolvedLocale,
+    // Also expose the raw locale for cases where you need it
+    locale,
+  };
+}