refactor(web): 前端改用 @stash/ui 组件库

- 新增本地依赖 @stash/ui（file:../../stash-ui），引入其 style.css 与设计令牌
- 页面骨架改用 Layout（contained + header/sider），搜索框改为吸顶
- 卡片/菜单/按钮/标签/头像/分页/空态/提示全部换成组件库组件
- 删除本地 iconfont 与 1400 行手写组件样式，App.css 只保留页面级样式
- 数据层、路由、过滤逻辑未改动；33 个 Rust 测试通过

stash-web/package-lock.json

@@ -8,6 +8,7 @@
       "name": "stash-web",
       "version": "0.0.0",
       "dependencies": {
+        "@stash/ui": "file:../../stash-ui",
         "react": "^19.3.1",
         "react-dom": "^19.3.1"
       },
@@ -21,6 +22,25 @@
         "vite": "^8.3.4"
       }
     },
+    "../../stash-ui": {
+      "name": "@stash/ui",
+      "version": "0.1.0",
+      "devDependencies": {
+        "@types/react": "^19.3.0",
+        "@types/react-dom": "^19.3.0",
+        "@vitejs/plugin-react": "^6.1.2",
+        "oxlint": "^1.88.0",
+        "playwright-core": "^1.64.1",
+        "react": "^19.3.1",
+        "react-dom": "^19.3.1",
+        "typescript": "~6.0.3",
+        "vite": "^8.3.4"
+      },
+      "peerDependencies": {
+        "react": ">=19",
+        "react-dom": ">=19"
+      }
+    },
     "node_modules/@oxc-project/types": {
       "version": "0.154.0",
       "resolved": "https://registry.npmmirror.com/@oxc-project/types/-/types-0.154.0.tgz",
@@ -616,6 +636,10 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/@stash/ui": {
+      "resolved": "../../stash-ui",
+      "link": true
+    },
     "node_modules/@types/node": {
       "version": "24.19.2",
       "resolved": "https://registry.npmmirror.com/@types/node/-/node-24.19.2.tgz",