Avoid the Bun 1.1.7 bug

[lhchavez]

Bun currently has a bug where raw FDs don't interact well with fs.createReadStream, and the result is that not all data is seen by the 'data' callback: oven-sh/bun#9907

This change is an egregious workaround that makes Rust read the file until the process closes it. It is suboptimal because of all the data copying that happens, and crossing the FFI barrier also takes some time, but at least this should let us not be completely blocked. Now there is one more (optional) argument to Pty that is a replacement of the 'data' callback.

~/ruspty$ cat test.js 
const { Pty } = require('./index');
const fs = require('fs');

const ENV = process.env;
const CWD = '.';

let firstread = true;

const pty = new Pty(
  'sh',
  [],
  ENV,
  CWD,
  { rows: 24, cols: 80 },
  (...result) => {
    console.log({ result });
    pty.close();
  },
  (err, chunk) => {
    if (err !== null) {
      throw err;
    }
    console.log(chunk.toString());
    if (firstread) {
      write.write('ls\n', () => {
        console.log('ls written');
        write.end('exit\n', () => {
          console.log('end done');
        });
      });
      firstread = false;
    }
  },
);

const write = fs.createWriteStream('', {
  fd: pty.fd(),
  autoClose: true,
});

write.on('close', () => {
  console.log('write close');
});

write.on('error', (err) => {
  if (err.code && err.code.indexOf('EIO') !== -1) {
    console.log('YAY');
  } else {
    console.log('write error', { err });
  }
});

console.log('gonna wait');
setTimeout(() => {
  console.log('done, hopefully');
}, 3000);
~/ruspty$ ./node_modules/.bin/bun --version 
1.1.7
~/ruspty$ ./node_modules/.bin/bun test.js 
gonna wait
sh-5.2$ 
ls written
end done
ls

exit

write close
1.0.26.txt  build.rs    index.js       package-lock.json          src
1.1.7.txt   bun.lockb   index.test.ts  package.json               target
Cargo.lock  flake.lock  node.txt       replit.nix                 test.js
Cargo.toml  flake.nix   node_modules   ruspty.linux-x64-gnu.node
README.md   index.d.ts  npm            rustfmt.toml

sh-5.2$ 
exit

{
  result: [ null, 0 ],
}
done, hopefully