feat: Windows NSIS installer, embedded icons, GUI auto-launch backend

- Add package/installer.nsi (Full/Server/Client) and toolchain.nsi
- Embed icon.ico (rounded corners) into homed.exe/waiter.exe via .syso
- GUI auto-launches homed.exe from parent dir (Windows only)
- GUI fallback connections.json from app resource dir
- Add initconfig command for config.db seeding
- Replace waiter rawmode* with raw_{unix,windows,other}.go
- Fix .gitignore: /homed instead of homed, add login.json
- Update icon.svg with rounded rect, new mascot.svg

cmd/gui/renderer/index.html

@@ -45,7 +45,7 @@
     <a onclick="switchTab('adapters')" data-i18n="navAdapters">适配器</a>
     <a onclick="switchTab('kernel')" data-i18n="navKernel">内核</a>
     <div style="margin-left:auto;display:flex;align-items:center;gap:8px">
-      <span id="conn-status" class="conn-indicator" onclick="openConnManager()" title="点击管理连接">
+      <span id="conn-status" class="conn-indicator" onclick="openConnManager()" title="点击管理连接 / Click to manage connections">
         <span class="status-dot dot-gray" id="conn-dot"></span>
         <span id="conn-name-display">未连接</span>
         <span style="font-size:10px;margin-left:4px;opacity:0.6">▼</span>