feat: initial frontend - React + TypeScript + Vite

- Login page with JWT auth
- Dashboard with stats and charts
- Issues list with pagination, filtering
- Issue detail with comments, status transitions
- Create issue form
- Dark theme UI
- Docker (nginx) with API proxy to backend
- Sidebar navigation

src/services/api.ts

@@ -0,0 +1,26 @@
+import axios from 'axios'
+
+const api = axios.create({
+  baseURL: '/api',
+})
+
+api.interceptors.request.use((config) => {
+  const token = localStorage.getItem('token')
+  if (token) {
+    config.headers.Authorization = `Bearer ${token}`
+  }
+  return config
+})
+
+api.interceptors.response.use(
+  (res) => res,
+  (err) => {
+    if (err.response?.status === 401) {
+      localStorage.removeItem('token')
+      window.location.href = '/login'
+    }
+    return Promise.reject(err)
+  }
+)
+
+export default api