Add Manual Competition Closure Button with Confirmation for Pending Settlement Status

1. Introduces a two-step tournament finalization process with a "Pending Settlement" state that allows administrators to review results before automatic winner notifications. This feature prevents disputes and provides oversight for tournament conclusions with manual confirmation capabilities.

2. Implements a manual tournament closure feature with visual status chips and confirmation-protected action buttons for tournaments in "Pending Settlement" status. Includes proper state validation, audit logging, and user confirmation flows to prevent accidental closures.