Reconcile schema with migrations and fix failed migration

- Align schema.prisma with add_15_features migration (15 discrepancies):
  nullability, column names, PKs, missing/extra columns, onDelete behavior
- Make universal_apply_programid migration idempotent for safe re-execution
- Add reconciliation migration for missing FKs and indexes
- Fix message.ts and mentor.ts to match corrected schema field names

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

prisma/migrations/20260208000000_add_missing_fks_indexes/migration.sql

@@ -0,0 +1,41 @@
+-- Reconciliation migration: Add missing foreign keys and indexes
+-- The add_15_features migration omitted some FKs and indexes that the schema expects
+-- This migration brings the database in line with the Prisma schema
+
+-- =====================================================
+-- Missing Foreign Keys
+-- =====================================================
+
+-- RoundTemplate → Program
+ALTER TABLE "RoundTemplate" ADD CONSTRAINT "RoundTemplate_programId_fkey"
+  FOREIGN KEY ("programId") REFERENCES "Program"("id") ON DELETE CASCADE ON UPDATE CASCADE;
+
+-- RoundTemplate → User (creator)
+ALTER TABLE "RoundTemplate" ADD CONSTRAINT "RoundTemplate_createdBy_fkey"
+  FOREIGN KEY ("createdBy") REFERENCES "User"("id") ON DELETE RESTRICT ON UPDATE CASCADE;
+
+-- Message → Round
+ALTER TABLE "Message" ADD CONSTRAINT "Message_roundId_fkey"
+  FOREIGN KEY ("roundId") REFERENCES "Round"("id") ON DELETE SET NULL ON UPDATE CASCADE;
+
+-- EvaluationDiscussion → Round
+ALTER TABLE "EvaluationDiscussion" ADD CONSTRAINT "EvaluationDiscussion_roundId_fkey"
+  FOREIGN KEY ("roundId") REFERENCES "Round"("id") ON DELETE CASCADE ON UPDATE CASCADE;
+
+-- ProjectFile → ProjectFile (self-relation for file versioning)
+ALTER TABLE "ProjectFile" ADD CONSTRAINT "ProjectFile_replacedById_fkey"
+  FOREIGN KEY ("replacedById") REFERENCES "ProjectFile"("id") ON DELETE SET NULL ON UPDATE CASCADE;
+
+-- =====================================================
+-- Missing Indexes
+-- =====================================================
+
+CREATE INDEX "RoundTemplate_roundType_idx" ON "RoundTemplate"("roundType");
+CREATE INDEX "MentorNote_authorId_idx" ON "MentorNote"("authorId");
+CREATE INDEX "MentorMilestoneCompletion_completedById_idx" ON "MentorMilestoneCompletion"("completedById");
+CREATE INDEX "Webhook_createdById_idx" ON "Webhook"("createdById");
+CREATE INDEX "WebhookDelivery_event_idx" ON "WebhookDelivery"("event");
+CREATE INDEX "Message_roundId_idx" ON "Message"("roundId");
+CREATE INDEX "EvaluationDiscussion_closedById_idx" ON "EvaluationDiscussion"("closedById");
+CREATE INDEX "DiscussionComment_discussionId_idx" ON "DiscussionComment"("discussionId");
+CREATE INDEX "DiscussionComment_userId_idx" ON "DiscussionComment"("userId");