feat: OpsxDB 桌面数据库客户端首版入库

含工作台/连库多引擎字段与 SSH·SSL、结果编辑、Redis 键浏览、
Tauri 桌面与 docs/落地页；排除本地构建产物与 sidecar 二进制。

apps/desktop/src-tauri/icons/android/mipmap-anydpi-v26/ic_launcher.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android">
+  <foreground android:drawable="@mipmap/ic_launcher_foreground"/>
+  <background android:drawable="@color/ic_launcher_background"/>
+</adaptive-icon>

apps/desktop/src-tauri/icons/android/values/ic_launcher_background.xml

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+  <color name="ic_launcher_background">#fff</color>
+</resources>

apps/desktop/src-tauri/icons/icon.svg

@@ -0,0 +1,7 @@
+<svg xmlns="http://www.w3.org/2000/svg" width="512" height="512" viewBox="0 0 512 512">
+  <rect width="512" height="512" rx="112" fill="#E11D2E"/>
+  <g transform="rotate(-20 256 256)">
+    <path d="M256 108 L290 216 L404 216 L312 286 L344 398 L256 332 L168 398 L200 286 L108 216 L222 216 Z"
+          fill="none" stroke="#FFFFFF" stroke-width="30" stroke-linejoin="round" stroke-linecap="round"/>
+  </g>
+</svg>