feat(content): 发布体系 大/小图 + 公开 + 园区端发布

- 迁移0018：content_items 加 card_mode/is_public/source/tenant_id
- ContentRepository：_to_dict/create/update 含新字段；list 加 public_only/tenant_id 过滤
- /opc/content 仅 published+公开；/opc/content/{id} 非公开→404
- 园区端 POST /park/api/content：发布人强制=园区名、source=carrier、tenant=本园、is_public 默认false(仅大屏)、card_mode默认small
- 园区端 GET /park/api/content：本园区内容(含未公开)供大屏
- schemas 补 card_mode/is_public

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

app/park/routers.py

@@ -1079,3 +1079,48 @@ async def carrier_company_compute(cid: str, body: CompanyComputeBody, user: dict
                 logging.getLogger(__name__).warning("企业配额发放失败 %s: %s", m.get("username"), exc)
     return {"ok": True, "company": updated, "quota_add": body.quota_add}
 
+
+
+# ==================== 园区端：发布资讯 + 大屏内容 ====================
+
+class ParkContentBody(BaseModel):
+    type: str = "news"
+    title: str
+    summary: str = ""
+    body: str = ""
+    cover: str = ""
+    video: str = ""
+    video_cover: str = ""
+    link: str = ""
+    card_mode: str = "small"   # 园区默认小图；运营端可改大/小图
+
+
+@router.post("/api/content", summary="园区端发布资讯（发布人=园区名，默认不公开）")
+async def carrier_publish_content(
+    body: ParkContentBody,
+    request: Request,
+    db=Depends(_carrier_db),
+    user: dict = Depends(_carrier_user),
+):
+    t = await _my_park(user)
+    item = await db.content.create({
+        "type": body.type, "title": body.title, "summary": body.summary, "body": body.body,
+        "cover": body.cover, "video": body.video, "video_cover": body.video_cover, "link": body.link,
+        "publisher_name": t["name"], "publisher_avatar": "",   # 发布人强制=园区名，不可改
+        "source": "carrier", "tenant_id": t["id"],
+        "card_mode": body.card_mode or "small",
+        "is_public": False,   # 默认不公开：仅本园区大屏；由运营端切公开
+        "status": "published",
+    })
+    await write_audit(db, action="content.publish", resource="content", resource_id=item["id"],
+                      detail=f"carrier {item['title']}", user=user, request=request)
+    return {"ok": True, "content": item}
+
+
+@router.get("/api/content", summary="园区资讯列表（本园区，含未公开，供大屏）")
+async def carrier_content_list(
+    db=Depends(_carrier_db),
+    user: dict = Depends(_carrier_user),
+):
+    t = await _my_park(user)
+    return {"items": await db.content.list(tenant_id=t["id"])}