Checkbox for Boolean inputs when triggering `workflow_dispatch`

**Is your feature request related to a problem? Please describe.**
When triggering a workflow via the view in vscode, the extension asks for input values. Currently, it generates an error when giving a string that is not `true` or `false` for boolean inputs.

**Describe the solution you'd like**
Use a checkbox input instead of a string input when asking vscode user for input.

**Additional context**
Add any other context or screenshots about the feature request here.

Start by locating the VS Code prompt used when triggering workflow_dispatch and the handling for boolean inputs; the issue does not name a file or test. Replace the string prompt behavior with a checkbox for boolean inputs, while preserving the existing workflow trigger flow, and verify that the resulting value is accepted as true or false.

索引モデルが issue の本文から書いたものです。