"Lua PSI Viewer" feature not working.

まだ誰も着手していません。

### Which OS are you using?

Linux

### Expected Behaviour

The "Lua PSI Viewer" feature, when ran, it expects some `index.html` file to be at this path:
~/.vscode/extensions/sumneko.lua-3.15.0-linux-x64/**client/web/dist/index.html**
but presumably the `index.html` file path actually exists here
~/.vscode/extensions/sumneko.lua-3.15.0-linux-x64/**client/webvue/build/index.html**

The error happens because of exactly this line:
https://github.com/LuaLS/vscode-lua/blob/9e91c07ce7b3b9fa162763b0eb7d39cf90033798/client/src/psi/psiViewer.ts#L18

so just do:
```diff
- private static readonly distDirectory = "client/web/dist";
+ private static readonly distDirectory = "client/webvue/build";
```

### Reproduction steps

Steps to reproduce:

Type: Lua PSI Viewer

get this error message:

### Additional Notes

the bug got introduces in ~3 years ago, by commit `1c7a326`

i actually dont know what this "Lua PSI Viewer" feature is for :P
Im curious to find out when it works (again)

Also, I was considering making this a pull request, but i dont know how to compile/run this project, so i cant test fix sry ):

client/src/psi/psiViewer.ts を調査し、特に distDirectory の値と PSI Viewer が index.html を解決する方法を確認してください。Command Palette から Lua PSI Viewer コマンドを再現し、パッケージ化された client/webvue/build/index.html のパスが使用されることを確認してください。viewer がファイル不足エラーなしで開けば完了です。

索引モデルが issue の本文から書いたものです。