fix: stop binding os.Stdin to sub commands

Binding os.Stdin, which will not be closed in gptscript, causes issues
with Windows because the subcommand will wait for stdin to be closed
before launching. Since we are not using stdin with subcommands, this
binding can safely be removed.

Signed-off-by: Donnie Adams <donnie@acorn.io>

Author: thedadams

pkg/engine/cmd.go

@@ -73,7 +73,6 @@ func (e *Engine) runCommand(ctx Context, tool types.Tool, input string, toolCate
 
 	output := &bytes.Buffer{}
 	all := &bytes.Buffer{}
-	cmd.Stdin = os.Stdin
 	cmd.Stderr = io.MultiWriter(all, os.Stderr)
 	cmd.Stdout = io.MultiWriter(all, output)