Fix the bug where the video does not stream to the end in Chrome

[schteeben95]

The video did not stream to the end. When Chrome requests for the last chunk it freezes and restarts the playback.

This new commit conforms to the RFC as explained here https://stackoverflow.com/questions/3303029/http-range-header

[devbaraus]

I made a few less modifications

async def video_endpoint(range: str = Header(None)):
    start, end = range.replace("bytes=", "").split("-")
    start = int(start)
    end = int(end) if end else start + CHUNK_SIZE_VIDEO
    
    with open(video_path, "rb") as video:
        video.seek(start)
        data = video.read(end - start)
        filesize = video_path.stat().st_size

        if end >= filesize:
            end = filesize - 1

        headers = {
            'Content-Range': f'bytes {str(start)}-{str(end)}/{str(filesize)}',
            'Accept-Ranges': 'bytes'
        }
        return Response(data, status_code=206, headers=headers, media_type="video/mp4")