Windows: default launch should use Windows Terminal (.bat), not raw .exe

[cy2311]

Title: Windows: default launch should use Windows Terminal (.bat), not
raw .exe

Body:

Problem
On Windows, double-clicking deepseek-tui-windows-x64.exe opens a
default cmd.exe window. The rendering is noticeably worse than Windows
Terminal — fonts, colors, and general feel are degraded. This is the
first impression for many Windows users.

Current workaround
Manually creating a .bat file:
bat @echo off set NO_ANIMATIONS=1 wt --title DeepSeek-TUI cmd /k "cd /d C:\Users\%USERNAME%\Desktop & deepseek-tui-windows-x64.exe"
This launches through Windows Terminal and the difference is night
and day.

Suggestion

1. Ship a deepseek-tui.bat alongside the .exe in Windows releases, or
2. Have the installer (if any) create a shortcut that invokes Windows
   Terminal, or
3. Consider a small launcher that detects and prefers wt.exe when
   available

Environment

• Version: 0.8.39
• OS: Windows (x64)