Abide the LSP better and actually run commands if completion items
request those:


https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#completionItem
```
/**
   * An optional command that is executed *after* inserting this completion.
   * *Note* that additional modifications to the current document should be
   * described with the additionalTextEdits-property.
   */
   command?: [Command](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#command);
```

Release Notes:

- N/A