feat: Custom confirm dialog for doc delete + improved empty state component

fix: New document starts empty instead of inheriting old content Previously createDocument() used getEditorText() to save current content into the new doc. Now it creates with empty string and calls loadDocumentText('') to clear the editor.

fix: Cancel on create document prompt now actually cancels

audit-v5: Complete ALL remaining green items - #8: Nav logo uses favicon.svg + clickable to home - #9: CTA button arrow indicator - #12: Word count goal (localStorage bayan_word_goal) - #13: Export summary as .txt file - #14: Character limit warning (already existed) - #15: Auto-save indicator in toolbar - #16: 404 page with Arabic numerals - #17: Loading skeleton animation for suggestions

authDone Ready for deployment