Update vault settings

{
  "id": "vault_abc123",
  "name": "Updated Contract Repository",
  "description": "Updated description",
  "filesBucket": "case-vault-files-abc123",
  "vectorBucket": "case-vault-vectors-abc123",
  "indexName": "contracts-index",
  "region": "us-east-1",
  "kmsKeyId": "arn:aws:kms:us-east-1:123456789:key/12345678-1234-1234-1234-123456789012",
  "chunkStrategy": {
    "method": "semantic",
    "overlap": 50,
    "chunkSize": 512,
    "minChunkSize": 100
  },
  "totalObjects": 1247,
  "totalBytes": 2847362048,
  "totalVectors": 45623,
  "metadata": {},
  "createdAt": "2024-01-01T00:00:00Z",
  "updatedAt": "2024-01-15T10:30:00Z"
}