Fix escaping repeated " for CMD

Rework escaping for CMD so that escaping a `"` works as follows

1. Escape the `"` itself (as `\\^"`) and inject a marker as a unique
   anchor for the required additional escaping of backslashes. The
   marker is guaranteed to be unique because we previously removed it
   indiscriminately from the argument.
2. Use the marker for further replacements. If it's preceded by `\\` it
   means the `\\` proceeds a `"` in the original string. If it's not it
   should still be removed.

Author: ericcornelissen

src/internal/win/cmd.js

@@ -13,14 +13,16 @@ import RegExp from "@ericcornelissen/lregexp";
 export function getEscapeFunction() {
   const controls = new RegExp("[\0\u0008\r\u001B\u009B]", "g");
   const newlines = new RegExp("\n", "g");
-  const quotes = new RegExp('(^|[^\\\\])(\\\\*)"', "g");
-  const specials = new RegExp('(["%&<>^|])', "g");
+  const specials = new RegExp("([%&<>^|])", "g");
+  const quotes = new RegExp('"', "g");
+  const backslashes = new RegExp("(^|[^\\\\])(\\\\*)\0", "g");
   return (arg) =>
     arg
       .replace(controls, "")
       .replace(newlines, " ")
-      .replace(quotes, '$1$2$2\\"')
-      .replace(specials, "^$1");
+      .replace(specials, "^$1")
+      .replace(quotes, '\0\\^"')
+      .replace(backslashes, "$1$2$2");
 }
 
 /**