feat(sites): extract douban IDs from list rows (audiences) (ID-3)

Co-Authored-By: Claude Opus 5.5 <[email protected]>

packages/adapters/src/sites/definitions/audiences.json

@@ -152,6 +152,16 @@
           }
         ]
       },
+      "doubanid": {
+        "selector": "a[href*=\"douban.com/subject/\"]",
+        "attribute": "href",
+        "filters": [
+          {
+            "name": "re_search",
+            "args": ["subject/(\\d+)", 1]
+          }
+        ]
+      },
       "freedate": {
         "selector": "img[class^=\"pro_\"]",
         "attribute": "title",