Release Notes:

  - Improved JSON syntax highlighting.

| Zed 0.174.6 | With this PR |
| --- | --- |
|
![Image](https://github.com/user-attachments/assets/46c8ae89-aca1-4756-b66c-78ccd8f3778d)
|
![Image](https://github.com/user-attachments/assets/3ba5e5db-1467-40d7-a502-2790feec8ad3)
|

- `null`: `constant` -> `constant.builtin`
- `,`, `:`: `punctuation.delimiter`

```json
{
  "property": null,
  "boolean": true
}
```