feat(server): refactor copilot (#14892)

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* **PR #14892** 👈

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packages/frontend/admin/src/config.json

@@ -313,10 +313,6 @@
       "type": "Boolean",
       "desc": "Whether to enable the copilot plugin. <br> Document: <a href=\"https://docs.affine.pro/self-host-affine/administer/ai\" target=\"_blank\">https://docs.affine.pro/self-host-affine/administer/ai</a>"
     },
-    "scenarios": {
-      "type": "Object",
-      "desc": "Use custom models in scenarios and override default settings."
-    },
     "providers.profiles": {
       "type": "Array",
       "desc": "The profile list for copilot providers."