Replace synchronous DOM manipulation with Web Worker + Svelte reactive state for recipe search. This moves text normalization and filtering off the main thread, ensuring zero input lag while typing. Search now runs in parallel with UI rendering, improving performance significantly for 240+ recipes.
- Add search.worker.js for background search processing
- Update Search.svelte to use Web Worker with $state runes
- Update +page.svelte with reactive filtering based on worker results
- Add language-aware recipe data synchronization for proper English/German search
- Migrate to Svelte 5 event handlers (onsubmit, onclick)
