[Bug]: TypeScript export declare JS emit is wrong

[robpalme]

Describe the bug

The JS emit for the TS code does not match upstream TypeScript.

• TS playground repro

Input code

export namespace ns {
    export declare let a: number;
    a = 1;
}

Config

No response

Playground link (or link to the minimal reproduction)

https://play.swc.rs/?version=1.10.3&code=H4sIAAAAAAAAA0utKMgvKlHIS8xNLS5ITE5VyCtWqOZSAIJUiExKanJOYlGqQk5qiUKilUJeaW5SapE1WEWigq2CoTVXLQBodLyZRAAAAA%3D%3D&config=H4sIAAAAAAAAA1VPOw7DIAzdOQXy3KFi6NA79BCIOhERAYQdqSjK3QsJpM1mv4%2Ff8yqkhIkMPOVaxrJEnQjTuReEsmf9KQhwjkgm2chw6yxTpQbtCHdoOxhgnUbk6kJSd6WaA1wIhN3RsNl6O%2BT%2FTBPmmJDoKqxS7UeH10TRUmEO72Un2y%2B179HgAT9RDzsPg6VXd3JaUGxfBMLf3xcBAAA%3D

SWC Info output

No response

Expected behavior

JS emit should be:

export var ns;
(function (ns) {
    ns.a = 1;
})(ns || (ns = {}));

Actual behavior

JS emit is invalid:

(function(ns) {
    a = 1;
})(ns || (ns = {}));
export var ns;

Version

1.10.3

Additional context

Similar to: rolldown/rolldown#3048