Detect tags and serve them in /is-valid
First tags to detect:
- webdataset
- croissant

`/is-valid` response will change from

```json
{
    "preview": true,
    "viewer": true,
    "search": true
    "filter": true
}
```

to

```json
{

    "preview": true,
    "viewer": true,
    "search": true
    "filter": true,
    "tags": ["croissant"]
}
```
Detect tags and serve them in /is-valid: First tags to detect:
- webdataset
- croissant

`/is-valid` response will change from

```json
{
    "preview": true,
    "viewer": true,
    "search": true
    "filter": true
}
```

to

```json
{

    "preview": true,
    "viewer": true,
    "search": true
    "filter": true,
    "tags": ["croissant"]
}
```