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

drizzle.config.ts

@@ -0,0 +1,13 @@
+import { defineConfig } from "drizzle-kit";
+import path from "node:path";
+
+const dataDir = process.env.DATA_DIR ?? path.join(process.cwd(), "data");
+
+export default defineConfig({
+  out: "./src/lib/db/migrations",
+  schema: "./src/lib/db/schema.ts",
+  dialect: "sqlite",
+  dbCredentials: {
+    url: path.join(dataDir, "db.sqlite"),
+  },
+});