Fix voting gate to use round status, make eval doc uploads toggleable

Voting check now uses round.status === ROUND_ACTIVE instead of requiring
windowOpenAt/windowCloseAt date range, fixing manual open/reopen scenarios.
Added requireDocumentUpload toggle (default off) to evaluation round config
so rounds reusing prior-round documents don't need file requirements.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/types/competition-configs.ts

@@ -83,6 +83,8 @@ export const EvaluationConfigSchema = z.object({
   feedbackMinLength: z.number().int().nonnegative().default(0),
   requireAllCriteriaScored: z.boolean().default(true),
 
+  requireDocumentUpload: z.boolean().default(false),
+
   coiRequired: z.boolean().default(true),
 
   peerReviewEnabled: z.boolean().default(false),