@graphile/simplify-inflection not using _schemaPrefix

### Summary

(for v5)

@graphile/simplify-inflection seems to ignore _schemaPrefix.

### Steps to reproduce

Here's a plugin that prefixes anything in the `foo` pg schema with `foo_`: https://gist.githubusercontent.com/danzho/fce5e8905c06745fb434e1f3a7530ba3/raw/6814300c61d20729af668c9803b5fb0155ed797a/foo-prefix-plugin.ts

With vanilla v5, this works as expected: `foo.user` -> `FooUser`. `allUsers` -> `allFooUsers`.

However, when you then add the @graphile/simplify-inflection inflector, single-/many-relation queries lose their schema prefix.

### Expected results

```graphql
fooUser {
fooKids
fooEmployer
}
```

### Actual results

```graphql
fooUser {
kids
employer
}
```

### Additional context

I could fix this for my needs by overriding `singleRelation` and `_manyRelation` to return `this.camelCase(relation.remoteResource.name)` since `relation.remoteResource.name` returns schema-prefixed values like `"foo_user"`.

Also, interestingly some relationships are correctly prefixed. In this case, a compound `(currency_id, store_id)` fk relation:

```graphql
fooUser {
fooCurrencyByCurrencyIdAndStoreId # <--
fooKidsByUserId
fooEmployerByEmployerId
}
```

Became this when using @graphile/simplify-inflection:

```graphql
fooUser {
fooCurrency # <--
kids
employer
}
```

(It stands out since it's the only one with the correct behavior, so there might be a special case that's accidentally working in the current impl)

Also I was sent here from discord: https://discord.com/channels/489127045289476126/498852330754801666/1349098001343189043