feat(infra): add docker image build and deploy pipeline (#13)

README.md

@@ -4,3 +4,10 @@ Telegram household finance bot and mini app built with Bun workspaces.
 
 See the [development setup runbook](docs/runbooks/dev-setup.md) for full setup,
 quality-check, and local development commands.
+
+For container smoke testing, run:
+
+```bash
+bun run docker:build
+bun run docker:smoke
+```