Invoke queue-triggered function bound to QueueMessage from admin endpoint

I am asking my question from #3011 again because the answer did not address my question before it was closed.

I specifically asked about functions that bind to `QueueMessage`. The answer @RohitRanjanMS gave was for binding to `string[]`.

If it **is not possible** to invoke a function that binds to `QueueMessage`, the documentation should say so. If it **is possible**, then the documentation should show what syntax should be used, because I don't think it's obvious.

---

What syntax do we use to invoke a queue-triggered function bound to QueueMessage using the local tools using the admin endpoint?

The [documentation](https://learn.microsoft.com/en-us/azure/azure-functions/functions-manually-run-non-http?tabs=azure-portal) says we should be able to use this syntax:

```
{ "input": "" }
```

But it's not clear what to put there. No matter what string I try to put there, I end up throwing JsonException from QueueMessageJsonConverter with the message "JSON payload must contain a MessageId".

I can see that the `input` I send seems to be received as the `MessageText` property in the JSON that QueueMessageJsonConverter is reading, but the `MessageId` property is always null in the JSON. I tried sending an object like this and none of the `MessageId` properties end up in QueueMessageJsonConverter:

```
new {
messageid = Guid.NewGuid().ToString(),
input = JsonSerializer.Serialize(new {
MessageId = Guid.NewGuid().ToString(),
MessageText = JsonSerializer.Serialize(new {
MessageId = Guid.NewGuid().ToString(),
this_is = "supposed to be the body of the QueueMessage",
})
}),
}
```

Start with the linked manual-run documentation and the QueueMessageJsonConverter behavior described in the issue. Reproduce the request through the local tools admin endpoint using a QueueMessage-bound function, then document the supported payload syntax or clearly state that the binding cannot be invoked this way.

Written by the indexing model from the issue text.