feat(web): management console frontend

Vue 3 + TS + Vite + Tailwind with self-built UI components. Landing,
auth, user dashboard (keys/usage/settings), and admin console
(overview/models/channels/users/usage/config). Theme system
(light/dark/system) with pre-paint boot script, theme-aware ECharts,
and a channel editor with multi-format (Anthropic/OpenAI) selection.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

web/package.json

@@ -0,0 +1,27 @@
+{
+  "name": "openteam-web",
+  "private": true,
+  "version": "0.1.0",
+  "type": "module",
+  "scripts": {
+    "dev": "vite",
+    "build": "vue-tsc --noEmit && vite build",
+    "preview": "vite preview",
+    "typecheck": "vue-tsc --noEmit"
+  },
+  "dependencies": {
+    "echarts": "^5.5.1",
+    "vue": "^3.5.13",
+    "vue-echarts": "^7.0.3",
+    "vue-router": "^4.4.5"
+  },
+  "devDependencies": {
+    "@vitejs/plugin-vue": "^5.2.1",
+    "autoprefixer": "^10.4.20",
+    "postcss": "^8.4.49",
+    "tailwindcss": "^3.4.14",
+    "typescript": "~5.6.3",
+    "vite": "^5.4.11",
+    "vue-tsc": "^2.1.10"
+  }
+}