fix: resolve all lint errors, improve type safety, and remove unused code

Remove unused imports, replace `any` types with proper interfaces in directus.ts
and i18n-loader.ts, exclude scripts/ and coverage/ from ESLint, and fix
unused variable warnings across the codebase.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

lib/i18n-loader.ts

@@ -5,20 +5,20 @@
  * - Caches results (5 min TTL)
  */
 
-import { getMessage, getContentPage } from './directus';
+import { getMessage, getContentPage, ContentPage } from './directus';
 import enMessages from '@/messages/en.json';
 import deMessages from '@/messages/de.json';
 
 const jsonFallback = { en: enMessages, de: deMessages };
 
 // Simple in-memory cache
-const cache = new Map<string, { value: any; expires: number }>();
+const cache = new Map<string, { value: unknown; expires: number }>();
 
-function setCached(key: string, value: any, ttlSeconds = 300) {
+function setCached(key: string, value: unknown, ttlSeconds = 300) {
   cache.set(key, { value, expires: Date.now() + ttlSeconds * 1000 });
 }
 
-function getCached(key: string): any | null {
+function getCached(key: string): unknown | null {
   const hit = cache.get(key);
   if (!hit) return null;
   if (Date.now() > hit.expires) {
@@ -38,7 +38,7 @@ export async function getLocalizedMessage(
 ): Promise<string> {
   const cacheKey = `msg:${key}:${locale}`;
   const cached = getCached(cacheKey);
-  if (cached !== null) return cached;
+  if (cached !== null) return cached as string;
 
   // Try Directus with requested locale
   const dbValue = await getMessage(key, locale);
@@ -84,11 +84,11 @@ export async function getLocalizedMessage(
 export async function getLocalizedContent(
   slug: string,
   locale: string
-): Promise<any | null> {
+): Promise<ContentPage | null> {
   const cacheKey = `page:${slug}:${locale}`;
   const cached = getCached(cacheKey);
-  if (cached !== null) return cached;
-  if (cached === null && cache.has(cacheKey)) return null; // Already checked, not found
+  if (cached !== null) return cached as ContentPage;
+  if (cache.has(cacheKey)) return null; // Already checked, not found
 
   // Try Directus with requested locale
   const dbPage = await getContentPage(slug, locale);
@@ -115,14 +115,18 @@ export async function getLocalizedContent(
  * Helper: Get nested value from object
  * Example: "nav.home" → obj.nav.home
  */
-function getNestedValue(obj: any, path: string): any {
+function getNestedValue(obj: Record<string, unknown>, path: string): string | null {
   const keys = path.split('.');
-  let value = obj;
+  let value: unknown = obj;
   for (const key of keys) {
-    value = value?.[key];
+    if (value && typeof value === 'object' && key in value) {
+      value = (value as Record<string, unknown>)[key];
+    } else {
+      return null;
+    }
     if (value === undefined) return null;
   }
-  return value;
+  return typeof value === 'string' ? value : null;
 }
 
 /**