Row permission check short-circuits on insert failure

### Version Information

Server Version: Tested on 2.20, 2.29 and 2.32
CLI Version (for CLI related issue):

### Environment

Docker

### What is the current behaviour?

Insert mutation fails with `uniqueness_violation`

### What is the expected behaviour?

Insert mutation to fail with row permission error

### How to reproduce the issue?

1. Load the attached metadata and postgres schema [pgdump and metadata.json.zip](https://github.com/hasura/graphql-engine/files/12398944/pgdump.and.metadata.json.zip)
2. try the insert in the screenshot below
3. Expect the hasura to check the permissions on a "visual" row. In this scenario, it would fail because the "label group" is not owned by the user.

This allows someone with knowledge of someone else's `user_id` to scan the database for that user's labels. A bit brute force, but 🤷🏾‍♂️

### Screenshots or Screencast

Text to copy paste

```gql
mutation A($obj: user_label_insert_input!){
insert_user_label_one(object:$obj){
label_group_id
}
}
```

```json
{
"obj": {
"label": "Secret",
"user_id": "855c2296-e296-4c07-bc5f-d36386b1f82f",
"label_group_id": "ab679f79-2109-4b89-bb47-db62b18d9771"
}
}
```

### Please provide any traces or logs that could help here.

N/A

### Any possible solutions/workarounds you're aware of?

N/A

### Keywords

hasura, brute force, row permissions, ai, generative ai (last two labels are just for prioritization)

Reproduce the insert mutation using the attached metadata and PostgreSQL schema, then trace how row permissions are evaluated when the insert encounters a uniqueness violation. Done means the mutation returns a row permission error for an unauthorized label group and no longer reveals information through the uniqueness response.

Written by the indexing model from the issue text.