### Description

`stats x = count`  throws error `unknown column [count]` which is confusing since stats does not allow aliasing for existing columns but only points to aggregate functions.
Hence why the message should be `incorrect function declaration count, you forgot to add the parantheisis`. 
Same approach when dealing with a typo: `stats x = cont(*)` - `Unkown aggregate function cont - did you mean count()?`

x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/analysis/VerifierTests.java
public void testMixedNumericalNonConvertibleTypesInIn() {
        assertEquals(
            "1:19: 2nd argument of [3 in (1, to_ul(3))] must be [integer], found value [to_ul(3)] type [unsigned_long]",
            error("from test | where 3 in (1, to_ul(3))")
        );
        assertEquals(
            "1:19: 1st argument of [to_ul(3) in (1, 3)] must be [unsigned_long], found value [1] type [integer]",
            error("from test | where to_ul(3) in (1, 3)")
        );
    }
    public void testUnsignedLongTypeMixInComparisons() {
        List<String> types = EsqlDataTypes.types()
            .stream()
            .filter(dt -> dt.isNumeric() && EsqlDataTypes.isRepresentable(dt) && dt != UNSIGNED_LONG)
            .map(DataType::typeName)
            .toList();
        for (var type : types) {
            for (var comp : List.of("==", "!=", ">", ">=", "<=", "<")) {
                String left, right, leftType, rightType;
                if (randomBoolean()) {
                    left = "ul";
                    leftType = "unsigned_long";
                    right = "n";
                    rightType = type;
                } else {
                    left = "n";
                    leftType = type;
                    right = "ul";
                    rightType = "unsigned_long";
                }