Fix CI failures: cross-env for Windows tests, CJS bundle for action runtime

Co-authored-by: shogo82148 <1157344+shogo82148@users.noreply.github.com>

Author: Copilot

action.yml

@@ -72,7 +72,7 @@ inputs:
 
 runs:
   using: "node24"
-  main: "dist/index.js"
+  main: "dist/index.cjs"
 branding:
   icon: "check-circle"
   color: "blue"