MVP-1: helpdesk core with dashboard, Telegram channel, customer portal

Next.js 16 + Drizzle/SQLite (matching ~/project-claude conventions), SSE-based
realtime updates, admin dashboard with status columns, ticket thread view,
Telegram long-polling integration (inbound + outbound), token-based customer
portal, Docker Compose packaging.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01QcXH24ky6zjk2UyK5oZUPH

scripts/generate-key.ts

@@ -0,0 +1,7 @@
+/**
+ * Generates a fresh AES-256-GCM key for CREDENTIALS_ENCRYPTION_KEY.
+ * Usage: npm run generate-key
+ */
+import crypto from "node:crypto";
+
+console.log(crypto.randomBytes(32).toString("base64"));