Question: `template-msc` number for `Reply` (not `in thread`)?

I would like to contribute by adding a template for `Reply` (not `in thread`), as suggested:

https://github.com/8go/matrix-commander/blob/79a5d0c2db9b3c49de0d0538affbe07f1a266f84/event-templates/README.md?plain=1#L21-L23

While I know how to get the correct JSON payload to send, I do not know how to get its `template-msc` number, even with [`matrix-spec-proposals`](https://github.com/matrix-org/matrix-spec-proposals/tree/cf3f0d58be2298f5022901c389e59d462c8d8796/proposals).

Example of such a payload according to Element desktop:

```json
{
"type": "m.room.message",
"content": {
"msgtype": "m.text",
"body": "> <@benjamin_loison:matrix.org> INITIAL_MESSAGE\n\nANSWER_MESSAGE",
"format": "org.matrix.custom.html",
"formatted_body": "

In reply to @benjamin_loison:matrix.org
INITIAL_MESSAGE

nANSWER_MESSAGE",
"m.relates_to": {
"m.in_reply_to": {
"event_id": "$CENSORED_1"
}
}
}
}
```

Giving me the correct `template-msc` number and explaining me how you found it would help me to contribute :)