AWS API Gateway returns 400 when {} are present in query values

## Context

What's your version of `nuqs`?

```
"nuqs": "2.5.2",
```

What framework are you using?

- ✅ Next.js (app router)

Which version of your framework are you using?

```
"next": "14.2.32",
```

## Description
- Requests to AWS API Gateway with `{}` in query values fail with 400 bad request (and appear to hard-crash the gateway, because no execution or access logs appear in CloudWatch for these requests)
- I am trying to use `parseAsJson`, which ends up serializing `{ hello: ['a', 'b'] }` as `{%22hello%22:[%22a%22,%22b%22]}`
- I expect `{}` to be URL-escaped into `%7B` and `%7D` respectively
- `:`, `[`, and `]` do not need to be escaped - AWS API Gateway works fine with those as-is

## Reproduction
- I do not have any public API Gateway services right now
- I could look into creating one if needed

## Related
- #1069
- #1068
- #925

查看 nuqs 原始碼中的 parseAsJson serializer，它可能位於類似 src/parsers.ts 或 src/serializer.ts 的檔案中。問題在於，將 JSON 物件序列化為查詢字串時，大括號 {} 沒有進行 URL 編碼。檢查該函式庫目前如何編碼查詢值，並將其與 URL 編碼標準進行比較。使用 Next.js 和模擬的 AWS API Gateway 端點建立最小重現，以驗證編碼後的值是否有效，藉此測試修正。

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