feat: add group filter to send logs view

- Add groupId query param to GET /api/logs endpoint
- Add group filter dropdown in SendLogs component
- Pass groups list and filter state from admin.vue
- Update useLogs.ts to accept optional groupId parameter
- Add groupId to SendRecord type
- Add i18n keys and CSS for filter UI

admin/types.ts

@@ -142,6 +142,7 @@ export interface SendRecord {
   id?: number;
   ts: number;
   routeId: string;
+  groupId?: string;
   event: string;
   repo?: string;
   target: string;