File handling

- Client(browser)  
    
    ```jsx
    const encryptedFileInput = document.getElementById("encryptedFileInput");
    const encryptedFile = encryptedFileInput.files[0];
    
    // Read the encrypted file
    const encryptedData = await encryptedFile.arrayBuffer();
    ```
- arrayBuffer vs blob
  blob is immutable and is the data type when we submit the file in form in client(browser)
  arraybuffer is the binary representation of file as thats how `fs.readFileSync` returns it