Cannot Install Older Version of Copilot CLI

### Describe the bug

I encountered an issue with the latest version of copilot cli and was trying to troubleshoot using older versions but the methods available seem to all install the latest version 0.398 no matter which version I specified

install script from `https://gh.io/copilot-install` using wget and curl + npm - even binary downloads directly from github are failing

Ill keep trying more options / version combos

### Affected version

GitHub Copilot CLI 0.0.398.

### Steps to reproduce the behavior
- Install latest via any method
- Uninstall copilot
- Specify a version during install using any method

```bash
➜ ~ copilot --version
GitHub Copilot CLI 0.0.398.
Run 'copilot update' to check for updates.
➜ ~ npm uninstall -g @github/copilot

removed 2 packages in 144ms
➜ ~ copilot --version
Cannot find GitHub Copilot CLI (https://docs.github.com/en/copilot/how-tos/set-up/install-copilot-cli)
Install GitHub Copilot CLI? ['y/N'] n
➜ ~ npm install -g @github/copilot@0.0.396
npm warn deprecated @github/copilot@0.0.396: A bug in this version caused invalid session id errors. We've fixed the bug in later versions

added 7 packages in 2s
➜ ~ copilot --version
GitHub Copilot CLI 0.0.398.
Run 'copilot update' to check for updates.
➜ ~ npm uninstall -g @github/copilot

removed 2 packages in 138ms
➜ ~ copilot --version
Cannot find GitHub Copilot CLI (https://docs.github.com/en/copilot/how-tos/set-up/install-copilot-cli)
Install GitHub Copilot CLI? ['y/N'] n
➜ ~ rm -f ~/.local/bin/copilot && bash -c 'export VERSION="v0.0.396"; curl -fsSL https://gh.io/copilot-install | bash'
Installing GitHub Copilot CLI...
Downloading from: https://github.com/github/copilot-cli/releases/download/v0.0.396/copilot-linux-x64.tar.gz
✓ Checksum validated
✓ GitHub Copilot CLI installed to /home/tcampbell/.local/bin/copilot

Installation complete! Run 'copilot help' to get started.
➜ ~ copilot --version
GitHub Copilot CLI 0.0.398.
Run 'copilot update' to check for updates
➜ ~ rm -f ~/.local/bin/copilot && cd /tmp && curl -L -o copilot-v0.0.396.tar.gz https://github.com/github/copilot-cli/releases/download/v0.0.396/copilot-linux-x64.tar.gz && tar -xzf copilot-v0.0.396.tar.gz && mv copilot ~/.local/bin/copilot && chmod +x ~/.local/bin/copilot && cd -
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
0 0 0 0 0 0 0 0 --:--:-- --:--:-- --:--:-- 0
100 56.0M 100 56.0M 0 0 39.5M 0 0:00:01 0:00:01 --:--:-- 51.6M
~
➜ ~ copilot --version
GitHub Copilot CLI 0.0.398.
Run 'copilot update' to check for updates.
➜ ~/ echo "6e877f6758792d98965eb1b6f2c7e3bb2d65401419f6c146860e86e641273ebc /tmp/copilot-v0.0.396.tar.gz" | sha256sum -c
/tmp/copilot-v0.0.396.tar.gz: OK
➜ ~
```

### Expected behavior

Specifying a version should install that version - not the latest version

### Additional context

OS: Windows 11 (WSL2 - Ubuntu 24.04.2 LTS)
Kernel: 6.6.87.2-microsoft-standard-WSL2
Node.js: v22.16.0
npm: 11.4.2
GitHub Copilot CLI: 0.0.398
Terminal: VS Code 1.108.2

[v396 checksums](https://github.com/github/copilot-cli/releases/download/v0.0.396/SHA256SUMS.txt)