Create a new ticket on the work board. New tickets start in the `backlog` where analysts pick them up for validation of the scope.
Parameters:
- `title`: short ticket title
- `description`: full ticket description
- `prerequisites`: optional ticket IDs that must finish before this ticket can be claimed
- `supersede`: optional ticket ID to replace/refine
- `priority` (Manager only): optional priority level (0 = highest urgency, 1 default, 2, 3, ... higher = lower). Maintainer must NOT include this parameter.
Ticket IDs may be given as a bare number (e.g. `123`) or the fully prefixed form (e.g. `workspace-123`); both refer to tickets in the current workspace only. IDs from other workspaces are rejected.
When `supersede` is provided, the old ticket is cancelled, this ticket is created as its replacement, and dependent prerequisites are rewired to the new ticket.