Clean up output from Batch files on Windows

[trgwii]

Batch is a funny language, and it has some weird quirks. One of these quirks is that it will output each line it executes before executing the line, UNLESS the line is pefixed with an "@" symbol.

Deno does not use an @ symbol in the generated .cmd files when installing scripts, resulting in this:

For the following generated file:

% generated by deno install %
deno.exe "run" "file:///C:/Users/Thomas/Documents/cowsay/cowsay.ts" %*

Simply adding an @ so the file appears like so:

% generated by deno install %
@deno.exe "run" "file:///C:/Users/Thomas/Documents/cowsay/cowsay.ts" %*

Results in the following output when executing an installed deno program:

I think this matches other platforms better, and matches closer to the way native executables execute on Windows as well.

I hope you'll consider merging this!

[CLAassistant]

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[ry]

LGTM - thanks for the explanation!