Unable to query a model where 2 associations use the same model

Nobody has claimed this yet.

Related: #1007

Say you have a model where it has 2 `belongs_to` and both of those associations are the same model (e.g. User), any query you do that requires both will only use 1 join and override any where clauses set.

```crystal
class Interview < BaseModel
table do
belongs_to interviewer : User
belongs_to interviewee : User
end
end

# I want to query for all interviews where the Interviewer isn't available for hire, but the Interviewee is
InterviewQuery.new
.where_interviewer(UserQuery.new.available_for_hire(false))
.where_interviewee(UserQuery.new.available_for_hire(true))
```

In this case, we end up getting this SQL which is not what I want

```sql
SELECT interviews.*
FROM interviews
INNER JOIN users ON interviews.interviewer_id = users.id
WHERE users.available_for_hire = 'false'
AND users.available_for_hire = 'true'
```

My initial thought is if we just always alias the joins to your association method name, then maybe it'll fix this. However, I think that may also be a breaking change for anyone using `where(raw_query : String)`.

So `where_interviewer` would go from

```
INNER JOIN users ON interviews.interviewer_id = users.id
```

to

```
INNER JOIN users AS interviewers ON interviews.interviewer_id = interviewers.id
```

But then anyone that was doing `where("users.something @> ?", ...)` would now get runtime errors since they would need to change it to `where("interviewers.something @> ?", ...)`.

Maybe we can use some annotation to turn on this change at compile time and give people time to swap over? I'm not sure how that would work. :thinking:

Start with the where_interviewer and where_interviewee query methods and reproduce the SQL shown in the issue using two belongs_to associations targeting User. Investigate how joins and raw where clauses are named; done means both associations can be queried independently without conflicting conditions while the compatibility impact of existing users[something] clauses is addressed.

Written by the indexing model from the issue text.