normalizeForIndex (lowercase + collapse whitespace runs incl. hard PDF/OCR
newlines + trim) and matchesNormalized so a query matches across the line breaks
in raw extracted text. Deliberately NO word-tokenization: Chinese has no
inter-word spaces, so substring match over normalized text is correct for both
Latin and CJK (段/word segmentation belongs in the DB FTS tokenizer). Verified
on CJK inputs (你好/笔记应用).
flutter analyze lib/editor clean; 181/181 tests (+9).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>