Fix cannot start ComfyUI: File not found

- Resolves various issues caused at different installation states, when PowerShell is not in PATH
- Forces standard env for all users - uses Windows PowerShell even if PS core is default

src/shell/util.ts

@@ -3,7 +3,8 @@ import os from 'node:os';
 export function getDefaultShell(): string {
   switch (os.platform()) {
     case 'win32':
-      return 'powershell.exe';
+      // Use full path to avoid e.g. https://github.com/Comfy-Org/desktop/issues/584
+      return `${process.env.SYSTEMROOT}\\System32\\WindowsPowerShell\\v1.0\\powershell.exe`;
     case 'darwin':
       return 'zsh';
     default: // Linux and others