feat: add RUN_SEED support and support_ticket_attachments migration

- New migration: create support_ticket_attachments table
- Dockerfile: RUN_SEED=true env var triggers seed after migrations

Dockerfile

@@ -39,4 +39,4 @@ COPY --from=builder /app/dist ./dist
 ENV NODE_ENV=production
 EXPOSE 3004
 ENTRYPOINT ["dumb-init", "--"]
-CMD ["sh", "-c", "cd packages/admin-db && npx prisma migrate deploy && cd /app && node dist/main.js"]
+CMD ["sh", "-c", "cd packages/admin-db && npx prisma migrate deploy && if [ \"$RUN_SEED\" = \"true\" ]; then echo 'Seeding admin database...' && npx tsx prisma/seed.ts; fi && cd /app && node dist/main.js"]

packages/admin-db/prisma/migrations/20260415000000_add_support_ticket_attachments/migration.sql

@@ -0,0 +1,24 @@
+-- CreateTable: support_ticket_attachments
+CREATE TABLE "support_ticket_attachments" (
+    "id"           TEXT NOT NULL,
+    "ticketId"     TEXT NOT NULL,
+    "commentId"    TEXT,
+    "fileName"     TEXT NOT NULL,
+    "originalName" TEXT NOT NULL,
+    "mimeType"     TEXT NOT NULL,
+    "sizeBytes"    INTEGER NOT NULL,
+    "uploadedBy"   TEXT NOT NULL,
+    "createdAt"    TIMESTAMP(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
+
+    CONSTRAINT "support_ticket_attachments_pkey" PRIMARY KEY ("id")
+);
+
+-- CreateIndex
+CREATE INDEX "support_ticket_attachments_ticketId_idx" ON "support_ticket_attachments"("ticketId");
+CREATE INDEX "support_ticket_attachments_commentId_idx" ON "support_ticket_attachments"("commentId");
+
+-- AddForeignKey
+ALTER TABLE "support_ticket_attachments" ADD CONSTRAINT "support_ticket_attachments_ticketId_fkey"
+  FOREIGN KEY ("ticketId") REFERENCES "support_tickets"("id") ON DELETE CASCADE ON UPDATE CASCADE;
+ALTER TABLE "support_ticket_attachments" ADD CONSTRAINT "support_ticket_attachments_commentId_fkey"
+  FOREIGN KEY ("commentId") REFERENCES "support_ticket_comments"("id") ON DELETE CASCADE ON UPDATE CASCADE;