feat(category): law 카테고리 분리 — enum + backfill + classify skip

- migrations/152: ALTER TYPE doc_category ADD VALUE 'law' (DDL only; PG16 단일-트랜잭션 제약상 backfill 은 별도)
- models/document.py: Enum 에 'law' 추가 (7 활성 + 3 유보)
- workers/law_monitor.py: Document(..., category='law') — 신규 유입부터 세팅
- workers/classify_worker.py: source_channel='law_monitor' early-return + 최소 필드 (ai_domain='법령', ai_tags=['법령'], importance='medium'). AI classify skip — 법령 구조 고정/외부 source of truth/자동 재수집
- scripts/backfill_category.py: law 분기 + WHERE re-target ((source_channel='law_monitor' AND category='document')) + VERIFY cat_law/law_source_count + fail 조건
- api/documents.py: default 목록 제외에 law_monitor 추가 (news 와 동일 패턴)
- api/dashboard.py: documents count FILTER 에 law_monitor 제외 (category_counts.law 는 기존 GROUP BY category 로 자동 노출)
- frontend/Sidebar.svelte: '법령 알림' 버튼 ?source=law_monitor → ?category=law (explicit category 경로가 default exclusion 을 skip)

plan: ~/.claude/plans/stateless-churning-raccoon.md
axis 원칙: category=UI 축, policy/telemetry=source_channel+ai_domain 축 (feedback_category_vs_ai_domain_axis.md)

배포 순서: push → GPU pull → compose up --build fastapi frontend → backfill --dry-run → --apply.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

scripts/backfill_category.py

@@ -1,13 +1,21 @@
 """§1 백필 — documents.category 전체 행 채우기.
 
 plan: luminous-sprouting-hamster.md §1
+확장: stateless-churning-raccoon.md (law 카테고리 분기 + idempotent 재실행)
 
-매핑 규칙 (category IS NULL 인 모든 행 대상):
+매핑 규칙:
+  source_channel='law_monitor'            → category='law'
   source_channel='news'                   → category='news'
   source_channel='memo'                   → category='memo'
+  file_type='note'                        → category='memo'
   user_tags 에 '@library/' 태그 보유      → category='library'
   그 외                                    → category='document'
 
+대상 WHERE:
+  category IS NULL
+  OR (source_channel='law_monitor' AND category='document')
+  — law 신규 enum 도입 전 backfill 로 'document' 배정됐던 206건 재분류.
+
 자동 library 전이 금지 — 기존 @library/ 태그 보유분만 'library' 로 이행.
 audio/video 는 §3 이후 생성 (백필 대상 없음).
 
@@ -36,6 +44,7 @@ WITH classified AS (
   SELECT
     id,
     CASE
+      WHEN source_channel = 'law_monitor'                             THEN 'law'
       WHEN source_channel = 'news'                                    THEN 'news'
       WHEN source_channel = 'memo'                                    THEN 'memo'
       WHEN file_type      = 'note'                                    THEN 'memo'
@@ -49,6 +58,7 @@ WITH classified AS (
     END AS target_category
   FROM documents
   WHERE category IS NULL
+     OR (source_channel = 'law_monitor' AND category = 'document')
 )
 SELECT target_category, COUNT(*) AS n FROM classified GROUP BY 1 ORDER BY 2 DESC;
 """
@@ -56,6 +66,7 @@ SELECT target_category, COUNT(*) AS n FROM classified GROUP BY 1 ORDER BY 2 DESC
 APPLY_SQL = """
 UPDATE documents
    SET category = CASE
+     WHEN source_channel = 'law_monitor'                             THEN 'law'::doc_category
      WHEN source_channel = 'news'                                    THEN 'news'::doc_category
      WHEN source_channel = 'memo'                                    THEN 'memo'::doc_category
      WHEN file_type      = 'note'                                    THEN 'memo'::doc_category
@@ -67,7 +78,8 @@ UPDATE documents
      )                                                                THEN 'library'::doc_category
      ELSE                                                                  'document'::doc_category
    END
- WHERE category IS NULL;
+ WHERE category IS NULL
+    OR (source_channel = 'law_monitor' AND category = 'document');
 """
 
 VERIFY_SQL = """
@@ -82,7 +94,9 @@ SELECT
          COALESCE(user_tags, '[]'::jsonb)
        ) AS t
        WHERE t LIKE '@library/%'
-     ))                                                                       AS has_library_tag;
+     ))                                                                       AS has_library_tag,
+  (SELECT COUNT(*) FROM documents WHERE category = 'law')                     AS cat_law,
+  (SELECT COUNT(*) FROM documents WHERE source_channel = 'law_monitor')       AS law_source_count;
 """
 
 DIST_SQL = """
@@ -138,11 +152,13 @@ async def run(apply: bool) -> int:
         # 4. verify
         print("\n=== 백필 후 검증 ===")
         row = (await session.execute(text(VERIFY_SQL))).one()
-        print(f"  all_rows         = {row.all_rows}")
-        print(f"  categorized      = {row.categorized}")
-        print(f"  uncategorized    = {row.uncategorized}")
-        print(f"  cat_library      = {row.cat_library}")
-        print(f"  has_library_tag  = {row.has_library_tag}")
+        print(f"  all_rows          = {row.all_rows}")
+        print(f"  categorized       = {row.categorized}")
+        print(f"  uncategorized     = {row.uncategorized}")
+        print(f"  cat_library       = {row.cat_library}")
+        print(f"  has_library_tag   = {row.has_library_tag}")
+        print(f"  cat_law           = {row.cat_law}")
+        print(f"  law_source_count  = {row.law_source_count}")
 
         fail = []
         if row.uncategorized != 0:
@@ -154,6 +170,11 @@ async def run(apply: bool) -> int:
                 f"cat_library={row.cat_library} != has_library_tag={row.has_library_tag} "
                 "(자동 전이 없음 정책 위반)"
             )
+        if row.cat_law != row.law_source_count:
+            fail.append(
+                f"cat_law={row.cat_law} != law_source_count={row.law_source_count} "
+                "(law_monitor 전체가 category='law' 여야 함)"
+            )
         if fail:
             print("\n!! 검증 실패:")
             for f in fail: