feat(rvw): Complete V2.0 Week 3 - Statistical validation extension and UX improvements

Week 3 Development Summary:

- Implement negative sign normalization (6 Unicode variants)

- Enhance T-test validation with smart sample size extraction

- Enhance SE triangle and CI-P consistency validation with subrow support

- Add precise sub-cell highlighting for P-values in multi-line cells

- Add frontend issue type Chinese translations (6 new types)

- Add file format tips for PDF/DOC uploads

Technical improvements:

- Add _clean_statistical_text() in extractor.py

- Add _safe_float() wrapper in validator.py

- Add ForensicsReport.tsx component

- Update ISSUE_TYPE_LABELS translations

Documentation:

- Add 2026-02-18 development record

- Update RVW module status (v5.1)

- Update system status (v5.2)

Status: Week 3 complete, ready for Week 4 testing
Co-authored-by: Cursor <cursoragent@cursor.com>

extraction_service/forensics/config.py

@@ -44,6 +44,12 @@ EFFECT_SIZE_PATTERN = re.compile(
     re.IGNORECASE
 )
 
+# 卡方值匹配，如 "χ²=57.519" 或 "2=57.519" 或 "χ2=57.519"
+CHI_SQUARE_PATTERN = re.compile(
+    r"(?:χ[²2]|[χx]2|2)\s*[=:]\s*(\d+\.?\d*)",
+    re.IGNORECASE
+)
+
 
 # ==================== 统计方法检测 ====================