Automatic 'First Setup' using flowforge.yml

### Description

Right now, when you bring up a FlowFuse instance, you have to go through a manual [First Setup process](https://flowfuse.com/docs/install/first-run/).

It would be great if flowfuse could use the config to skip the manual entry:

(environment variable expansion needed for security/portability)
```yaml

admin:
full_name: $ADMIN_NAME
email: $ADMIN_EMAIL
username: $ADMIN_USERNAME
password: $ADMIN_PASSWORD

settings:
license_key: $LICENSE_KEY
enable_anonymous_statistics: true

teams:
- name: Dev
applications:
- name: Ingestion
description: Data Ingestion
# create_instance: true
# instance_name: auto
# instance_type: default
# instance_stack: default

# NodeRed Projects:
project_repo: git@github.com:user/my-node-red-projects-repo.git
# project_branch: main
```
Scripting it doesn't seem like the right way to go since the endpoints use crsf tokens and I assume those checks are already being done during the bring up process.

### Which customers would this be available to

Everyone - CE/Starter/Team/Enterprise

### Have you provided an initial effort estimate for this issue?

I am not a FlowFuse team member