[release/9.0] Avoid using ^ and ~ when invalid because of value converters

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Fixes #35093
Backports #35124

Description

EF 9 brings many improvements to SQL generation (list). One of these, which also improves query performance, applies bit arithmetic (XOR) to implement equality in contexts where SQL Server requires a BIT value (as opposed to a search condition, so projected SELECT values rather than WHERE predicates).

Unfortunately, the SQL optimization was implemented too widely, applying also on value-converted values, which is incorrect.

Customer impact

Queries on SQL Server which involve equality with a value-converted value sometimes generate invalid SQL and fail. For example:

_ = await context.Orders
    .Select(order => new { Paid = order.State == OrderState.Paid })
    // The following is OK (non-value-converted string)
    // .Select(order => new { IsNameFoo = order.Name == "Foo" })
    .ToListAsync();

This scenario is particularly common with value-converted enums, and so has the potential to affect many users. The fix is trivial and low-risk.

How found

Customer reported on 9.

Regression

Yes, from 8.

Testing

Tests added.

Risk

Low and quirked.

/cc @ranma42

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Servicing approved via email.