feat(i18n): deprecate Spanish language support in the frontend

frontend/src/stores/languageStore.js

@@ -1,31 +1,38 @@
-import { defineStore } from 'pinia'
-import { useSessionStorage } from '@vueuse/core'
-import { useI18n } from 'vue-i18n'
+import { defineStore } from 'pinia';
+import { useSessionStorage } from '@vueuse/core';
+import { useI18n } from 'vue-i18n';
 
-export const useLanguageStore = defineStore(
-    'language',
-    () => {
-        // Initialize with the stored value or default to 'fr'
-        const storedLocale = useSessionStorage('user-locale', 'fr')
-        
-        // Get i18n instance
-        const { locale } = useI18n()
-        
-        // Set the initial locale from storage
-        if (locale && storedLocale.value) {
-            locale.value = storedLocale.value
-        }
-        
-        function setLocale(newLocale) {
-            if (locale) {
-                locale.value = newLocale
-            }
-            storedLocale.value = newLocale
-        }
-        
-        return {
-            locale: storedLocale,
-            setLocale
-        }
+const ALLOWED_LOCALES = ['en', 'fr'];
+const DEFAULT_LOCALE = 'fr';
+
+export const useLanguageStore = defineStore('language', () => {
+    const storedLocale = useSessionStorage('user-locale', DEFAULT_LOCALE);
+
+    // Get i18n instance (provided globally)
+    const { locale } = useI18n();
+
+    function sanitizeLocale(value) {
+        return ALLOWED_LOCALES.includes(value) ? value : DEFAULT_LOCALE;
     }
-) 
+
+    // Initialize locale with a sanitized value
+    const initial = sanitizeLocale(storedLocale.value);
+    storedLocale.value = initial;
+    if (locale) {
+        locale.value = initial;
+    }
+
+    function setLocale(newLocale) {
+        const next = sanitizeLocale(newLocale);
+        if (locale) {
+            locale.value = next;
+        }
+        storedLocale.value = next;
+    }
+
+    return {
+        locale: storedLocale,
+        setLocale,
+        allowedLocales: ALLOWED_LOCALES,
+    };
+});