fix: resolve all 1008 svelte-check type errors across codebase

Add type annotations, JSDoc types, null checks, and proper generics
to eliminate all svelte-check errors. Key changes include:
- Type $state(null) variables to avoid 'never' inference
- Add JSDoc typedefs for plain <script> components
- Fix mongoose model typing with Model<any> to avoid union complexity
- Add App.Error/App.PageState interfaces in app.d.ts
- Fix tuple types to array types in types.ts
- Type catch block errors and API handler params
- Add null safety for DOM queries and optional chaining
- Add standard line-clamp property alongside -webkit- prefix

src/lib/offline/sync.ts

@@ -166,8 +166,8 @@ async function precacheRecipeData(recipes: BriefRecipeType[]): Promise<void> {
 		dataUrls.push(`/rezepte/${recipe.short_name}/__data.json`);
 
 		// English recipe data (if translation exists)
-		if (recipe.translations?.en?.short_name) {
-			dataUrls.push(`/recipes/${recipe.translations.en.short_name}/__data.json`);
+		if ((recipe as any).translations?.en?.short_name) {
+			dataUrls.push(`/recipes/${(recipe as any).translations.en.short_name}/__data.json`);
 		}
 
 		// Collect metadata for subroute caching