fix(ui): harden bootstrap locale fallback

packages/ui/src/lib/i18n/index.tsx

@@ -117,9 +117,15 @@ async function loadLocaleMessages(locale: Locale): Promise<Messages> {
 
 export async function preloadLocaleMessages(preferredLocale?: string | null): Promise<Locale> {
   const resolvedLocale = matchSupportedLocale(preferredLocale ?? undefined) ?? detectNavigatorLocale() ?? "en"
-  globalMessages = await loadLocaleMessages(resolvedLocale)
-  setGlobalRevision((value) => value + 1)
-  return resolvedLocale
+  try {
+    globalMessages = await loadLocaleMessages(resolvedLocale)
+    setGlobalRevision((value) => value + 1)
+    return resolvedLocale
+  } catch {
+    globalMessages = enMessages
+    setGlobalRevision((value) => value + 1)
+    return "en"
+  }
 }
 
 export function tGlobal(key: string, params?: TranslateParams): string {

packages/ui/src/lib/ui-bootstrap-cache.ts

@@ -1,8 +1,8 @@
 export type UiBootstrapTheme = "light" | "dark" | "system"
 
 export interface UiBootstrapCacheSnapshot {
-  theme?: UiBootstrapTheme
-  locale?: string
+  theme?: UiBootstrapTheme | null
+  locale?: string | null
 }
 
 const UI_BOOTSTRAP_CACHE_KEY = "codenomad:ui-bootstrap"
@@ -41,7 +41,18 @@ export function writeUiBootstrapCache(snapshot: UiBootstrapCacheSnapshot) {
   }
 
   try {
-    window.localStorage.setItem(UI_BOOTSTRAP_CACHE_KEY, JSON.stringify(snapshot))
+    const previous = readUiBootstrapCache()
+    const next: UiBootstrapCacheSnapshot = {
+      theme: snapshot.theme === undefined ? previous.theme : snapshot.theme ?? undefined,
+      locale: snapshot.locale === undefined ? previous.locale : snapshot.locale ?? undefined,
+    }
+
+    if (!next.theme && !next.locale) {
+      window.localStorage.removeItem(UI_BOOTSTRAP_CACHE_KEY)
+      return
+    }
+
+    window.localStorage.setItem(UI_BOOTSTRAP_CACHE_KEY, JSON.stringify(next))
   } catch {
     /* noop */
   }

packages/ui/src/stores/preferences.tsx

@@ -600,10 +600,17 @@ const configContextValue: ConfigContextValue = {
 
 export const ConfigProvider: ParentComponent = (props) => {
   createEffect(() => {
+    if (!isLoaded()) {
+      return
+    }
+
     const bucket = uiConfigBucket()
+    const theme = bucket.theme
+    const locale = bucket.settings?.locale
+
     writeUiBootstrapCache({
-      theme: bucket.theme,
-      locale: bucket.settings?.locale,
+      theme: theme ?? null,
+      locale: locale ?? null,
     })
   })