Expression shorthands

experiment k !21 (comment 87753)

// expr() shorthand
$year = static fn(Expression $e) => expr(new IntType(), "EXTRACT('year' FROM ?)", $e);

$table–>findBy([
    $table->value()->is(greaterThanOrEqualTo(42)),
    $year($table->issuedAt())->is(equalTo(2021)), // all expressions have is() method
], orderBy: [
    $table->value()->descending(), // all expressions have ascending()/descending() methods
]);