- reduces unnecessary shallow copying within operations by removing
unnecessary spreads or .map()'s
- removes unnecessary `deleteMany` call in `deleteUserPreferences` for
auth-enabled collections
- replaces all instances of `validOperators.includes` with
`validOperatorMap[]`. O(n) => O(1)
- optimizes the `sanitizeInternalFields` function. Previously, it was
doing a **lot** of shallow copying