List vault objects

{
  "vaultId": "vault_abc123",
  "objects": [
    {
      "id": "obj_xyz789",
      "filename": "contract_2024_v2.pdf",
      "contentType": "application/pdf",
      "sizeBytes": 2485760,
      "ingestionStatus": "completed",
      "pageCount": 15,
      "textLength": 12450,
      "chunkCount": 28,
      "vectorCount": 28,
      "tags": [
        "contract",
        "2024",
        "vendor"
      ],
      "metadata": {
        "client": "Acme Corp",
        "matter": "M-2024-001"
      },
      "createdAt": "2024-01-15T10:30:00Z",
      "ingestionCompletedAt": "2024-01-15T10:32:15Z"
    }
  ],
  "count": 1
}