Initial scaffold: FastAPI backend + Vue 3 frontend + Docker setup

Backend: config/db/security/logging core, SQLAlchemy models (Server,
Credential, UpdateJob, UpdateLog, AuditLog, User), services (winrm, ssh,
cau, audit, job_runner), REST API (auth, servers, updates, audit),
Socket.io WebSocket layer.
Frontend: Vue 3 + TS + Pinia + Tailwind, Views (Dashboard, Servers,
Updates, Audit, Login), axios + socket.io-client, nginx prod config.

frontend/tailwind.config.js

@@ -0,0 +1,8 @@
+/** @type {import('tailwindcss').Config} */
+export default {
+  content: ['./index.html', './src/**/*.{vue,ts}'],
+  theme: {
+    extend: {},
+  },
+  plugins: [require('@tailwindcss/forms')],
+}