[ASDAlexander77]

"a" in 5 compiled with no diagnostic and was false: the field lookup on a number found nothing.

Fix: mlirGenInLogic rejects a number, boolean or bigint (literal or enum types included) on the right of in, at the right operand, with TypeScript's message.

Repro (diagnostic-location/in_primitive.ts):

function main() {
    const s = "hello";
    print("length" in s);
    print("a" in 5);   // 7:18: error: The right-hand side of an 'in' expression must not be a primitive: '5'
}

Kept on purpose: a string on the right ("length" in s, asserted by tests/00in_method_names.ts). TypeScript rejects it too, but the corpus treats it as an extension. Line 6 of the test must stay error-free.

ctest -C Release -j 8 --timeout 300: 100% passed, 0 failed (4092 tests on this branch).

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