Config for setting collation for attributes

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### Is your feature request related to a problem? Please describe.

When working with a shared PostgreSQL database that's also used by Django (since [Django 4.2's deprecation of ](https://docs.djangoproject.com/en/5.2/releases/4.2/#features-deprecated-in-4-2)CITextField), you can't use ilike filters anymore on columns that Django has set up with nondeterministic collations.
Django deprecated CITextField and now prefers setting db_collation on regular text fields to handle case-insensitive comparisons. The problem is that when Django creates a column with one of these nondeterministic collations, PostgreSQL throws errors if you try to use LIKE or ILIKE operators on those columns.

To Reproduce

Have a Django app that creates a table with a text field using db_collation for case-insensitive matching
Try to query that table from Ash/Ecto using an ILIKE filter
PostgreSQL will error because ILIKE doesn't work with nondeterministic collations

### Describe the solution you'd like

It would be nice to have a way to specify a collation on an Ash attribute that gets applied at the query level (not in migrations - we can't change the column definition since that would break Django). Something that would generate SQL like:

```sql
WHERE column_name COLLATE "default" ILIKE '%search%'
```

This way Ash could work with Django's collation setup without modifying the actual column definitions.

### Describe alternatives you've considered

_No response_

### Additional context

_No response_