cuvs-java: Fix, document, and test BruteForceQuery.Builder::withPrefilter

This issue has been filed to evaluate the pre-filter for `BruteForceQuery`.

I have been unsuccessful in getting it to work, and am unsure how it is supposed to work. For example,

```
var queryBuilder = new BruteForceQuery.Builder()
   .withPrefilter(new long[] { 0b1001L });
```

Should this filter out vectors at ordinal 1 and 2? In my testing it does not.