feat: 접근성 검사 표준 선택 기능 — WCAG/KWCAG 버전별 선택 지원

3가지 검사 모드(한 페이지, 사이트 크롤링, 목록 업로드) 모두에서 접근성 표준을
선택할 수 있도록 추가. WCAG 2.0 A/AA, 2.1 AA, 2.2 AA와 KWCAG 2.1, 2.2를
지원하며, KWCAG 선택 시 axe-core 결과를 KWCAG 검사항목으로 자동 매핑.

- KWCAG 2.2 (33항목) / 2.1 (24항목) ↔ WCAG 매핑 테이블 (kwcag_mapping.py)
- AccessibilityChecker에 표준 파싱 및 KWCAG 변환 로직 추가
- 전체 API 파이프라인에 accessibility_standard 파라미터 전파
- 프론트엔드 3개 폼에 공용 표준 선택 드롭다운 추가

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

backend/app/routers/batch_inspections.py

@@ -73,6 +73,7 @@ async def start_batch_inspection(
     file: UploadFile = File(...),
     name: str = Form(...),
     concurrency: int = Form(default=4),
+    accessibility_standard: str = Form(default="wcag_2.1_aa"),
 ):
     """
     Start a new batch inspection from an uploaded URL file.
@@ -154,6 +155,7 @@ async def start_batch_inspection(
             name=name,
             urls=urls,
             concurrency=concurrency,
+            accessibility_standard=accessibility_standard,
         )
     except Exception as e:
         logger.error("Failed to start batch inspection: %s", str(e))

backend/app/routers/inspections.py

@@ -55,7 +55,10 @@ async def start_inspection(request: StartInspectionRequest):
     service = _get_service()
 
     try:
-        inspection_id = await service.start_inspection(url)
+        inspection_id = await service.start_inspection(
+            url,
+            accessibility_standard=request.accessibility_standard,
+        )
     except httpx.HTTPStatusError as e:
         raise HTTPException(
             status_code=400,

backend/app/routers/site_inspections.py

@@ -67,6 +67,7 @@ async def start_site_inspection(request: StartSiteInspectionRequest):
             max_pages=request.max_pages,
             max_depth=request.max_depth,
             concurrency=request.concurrency,
+            accessibility_standard=request.accessibility_standard,
         )
     except httpx.HTTPStatusError as e:
         raise HTTPException(