feat: 사이드바 3단계 재귀 트리 + 너비 확장 (320px)

- tree API: domain 경로를 파싱하여 계층 구조로 반환
  (Industrial_Safety → Practice → Patrol_Inspection)
- Sidebar: 재귀 snippet으로 N단계 트리 렌더링
- domain 필터: prefix 매칭 (상위 클릭 시 하위 전부 포함)
- 사이드바 너비: 260px → 320px

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

app/api/documents.py

@@ -78,47 +78,59 @@ class DocumentUpdate(BaseModel):
 # ─── 스키마 (트리) ───
 
 
-class SubGroupNode(BaseModel):
-    sub_group: str
+class TreeNode(BaseModel):
+    name: str
+    path: str
     count: int
-
-
-class DomainNode(BaseModel):
-    domain: str
-    count: int
-    children: list[SubGroupNode]
+    children: list["TreeNode"]
 
 
 # ─── 엔드포인트 ───
 
 
-@router.get("/tree", response_model=list[DomainNode])
+@router.get("/tree")
 async def get_document_tree(
     user: Annotated[User, Depends(get_current_user)],
     session: Annotated[AsyncSession, Depends(get_session)],
 ):
-    """도메인/sub_group 트리 (사이드바용)"""
+    """도메인 트리 (3단계 경로 파싱, 사이드바용)"""
     from sqlalchemy import text as sql_text
 
     result = await session.execute(
         sql_text("""
-            SELECT ai_domain, ai_sub_group, COUNT(*)
+            SELECT ai_domain, COUNT(*)
             FROM documents
-            WHERE ai_domain IS NOT NULL
-            GROUP BY ai_domain, ai_sub_group
-            ORDER BY ai_domain, ai_sub_group
+            WHERE ai_domain IS NOT NULL AND ai_domain != ''
+            GROUP BY ai_domain
+            ORDER BY ai_domain
         """)
     )
 
-    tree: dict[str, DomainNode] = {}
-    for domain, sub_group, count in result:
-        if domain not in tree:
-            tree[domain] = DomainNode(domain=domain, count=0, children=[])
-        tree[domain].count += count
-        if sub_group:
-            tree[domain].children.append(SubGroupNode(sub_group=sub_group, count=count))
+    # 경로를 트리로 파싱
+    root: dict = {}
+    for domain_path, count in result:
+        parts = domain_path.split("/")
+        node = root
+        for part in parts:
+            if part not in node:
+                node[part] = {"_count": 0, "_children": {}}
+            node[part]["_count"] += count
+            node = node[part]["_children"]
 
-    return list(tree.values())
+    def build_tree(d: dict, prefix: str = "") -> list[dict]:
+        nodes = []
+        for name, data in sorted(d.items()):
+            path = f"{prefix}/{name}" if prefix else name
+            children = build_tree(data["_children"], path)
+            nodes.append({
+                "name": name,
+                "path": path,
+                "count": data["_count"],
+                "children": children,
+            })
+        return nodes
+
+    return build_tree(root)
 
 
 @router.get("/", response_model=DocumentListResponse)
@@ -136,9 +148,8 @@ async def list_documents(
     query = select(Document)
 
     if domain:
-        query = query.where(Document.ai_domain == domain)
-    if sub_group:
-        query = query.where(Document.ai_sub_group == sub_group)
+        # prefix 매칭: Industrial_Safety 클릭 시 하위 전부 포함
+        query = query.where(Document.ai_domain.startswith(domain))
     if source:
         query = query.where(Document.source_channel == source)
     if format: