Unify Ticket and Event creation, to ensure consistency on the different categories.
Use causality category instead of aggregate, to link the Ticket to the context document (instance, node, ...).
Aggregate must be used to define the item of the movement resource.

Monitoring: the tickets are managed by the virtual master admin,
who is responsible to provide a good service quality.
Admin will use their worklist to see the ongoing tickets.

Regularisation Request: this ticket is handle by the accounting team.
Unpaid invoice can be related to any kind of service (instance, node), which
have only 2 states from the ticket point of view: running or destroyed.
Only check the automated ledger, do not be impacted by other kind of invoices.

Prevent allocation if a customer has an ongoing Regularisation Request.

TODO: handle case of unpaid invoices for professional customers

Also in this commit:
* drop templates
* use interaction workflow to trigger alarms