str produces unexpected pointer behavior

[LunaStev]

When using the & operator on a str variable, Wave produces unexpected results.
Currently, str is internally treated as an i8*, so applying & creates a pointer-to-pointer (i8**).
This leads to confusing output instead of the expected string address or string content.

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Steps to Reproduce

1. Create a file test/test40.wave with the following code:

fun main() {
    var msg: str = "Hello";
    var msg_ptr: ptr<str> = &msg;
    var msg_ptr2: ptr<i8> = &msg;

    println("{}", msg_ptr);
    println("{}", msg_ptr2);
}

2. Run

cargo run -- run test/test40.wave

3. Output

0x7fffdda81078
�"e

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Expected Behavior

• &msg should either be:
  • Valid pointer to the string data ("Hello"), or
  • Disallowed by the compiler if str is already a pointer type.

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Actual Behavior

• &msg creates a pointer-to-pointer (i8**), resulting in unexpected values being printed.