pub fn read_public_values_slice(&mut self, buf: &mut [u8]) {
        let len = buf.len();
        let start = self.state.public_values_stream_ptr;
        let end = start + len;
        assert!(end <= self.state.public_values_stream.len());
        buf.copy_from_slice(&self.state.public_values_stream[start..end]);
        self.state.public_values_stream_ptr = end;
    }
Read a slice of bytes from the public values stream.
crates/core/executor/src/io.rs