No GitHub repositories found when using SSH aliases

首先跟踪扩展激活过程以及 GitHub 上下文查找；当 remote 使用非 github.com 的 SSH 别名时，该查找会因 Invalid URL 而失败。使用 issue 中描述的 SSH 配置和 remote 形式复现问题，然后验证仓库发现功能对带别名的 GitHub remote 和标准 GitHub remote 都能正常工作。

Describe the bug
When using SSH config aliases (see the example below), the GitHub Actions extension returns the error message "No GitHub repositories found". SSH aliases are often used when a user has multiple GitHub accounts that have separate SSH keys.

This only occurs when using an alias that does not include github.com in the alias name. If I were to change the alias name to, for example, personal.github.com, as well as the remote, then the extension works without issue.

To Reproduce
Steps to reproduce the behavior:

1. Create an alias in your SSH config file (e.g., ~/.ssh/config) with any name that does not include github.com.
2. Switch your origin remote to use the alias (e.g., git@alias:username/repo.git)
3. Reload VSCode
4. Switch to the GitHub Actions extension and see "No GitHub repositories found"
5. Switch your origin remote back to a standard "github.com" alias
6. Reload VSCode
7. Switch to the GitHub Actions extension and see standard functionality.

Expected behavior
GitHub Actions would work regardless of the SSH config alias.

Extension Version
v0.27.2

Additional context
Logs from the extension when using a non-github.com alias:

Activating GitHub Actions extension...
Error getting GitHub context
Invalid URL
TypeError: Invalid URL
	at new URL (node:internal/url:818:25)
	at /Users/josephgruber/.vscode/extensions/github.vscode-github-actions-0.27.2/dist/extension-node.js:1:1158030
	at async Promise.all (index 0)
	at async /Users/josephgruber/.vscode/extensions/github.vscode-github-actions-0.27.2/dist/extension-node.js:1:1157669
	at async De (/Users/josephgruber/.vscode/extensions/github.vscode-github-actions-0.27.2/dist/extension-node.js:1:1157518)
	at async os (/Users/josephgruber/.vscode/extensions/github.vscode-github-actions-0.27.2/dist/extension-node.js:1:1339675)
	at async Lb.n (file:///Applications/Visual%20Studio%20Code.app/Contents/Resources/app/out/vs/workbench/api/node/extensionHostProcess.js:112:13382)
	at async Lb.m (file:///Applications/Visual%20Studio%20Code.app/Contents/Resources/app/out/vs/workbench/api/node/extensionHostProcess.js:112:13345)
	at async Lb.l (file:///Applications/Visual%20Studio%20Code.app/Contents/Resources/app/out/vs/workbench/api/node/extensionHostProcess.js:112:12801)