Enabling SDK extensions doesn't seem to affect PATH

I enable all SDK extensions by defining below env var inside Flatseal.

`FLATPAK_ENABLE_SDK_EXT=*`

If I run vscode from CLI, I can see the `Enabling SDK extension` messages `code.sh` prints. However when I open a new Terminal inside Flatpak, I can't see PATH changes the script does.

I've installed Rust SDK extension and I can only use it if I define the following PATH env var inside Flatseal:

```
PATH=/usr/bin:/app/bin:/usr/lib/sdk/rust-stable/bin
```

I expected vscode to work without explicitly defining PATH.

从 code.sh 入口点开始，通过在 Flatseal 中启用 FLATPAK_ENABLE_SDK_EXT=*、启动 VS Code 并打开一个新的 Flatpak Terminal 来重现该问题。比较 code.sh 使用的 PATH 与 Terminal 继承的环境。完成标准是：Rust SDK 扩展的 bin 目录无需手动设置 PATH 即可在 PATH 中使用。

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