-> setup platform.io based development with tests
    - re-write tests with unity



- backend
    /api/session/start
    /api/session/finish
    /api/session/data?startIndex=25 (returns nothing if no session is active)
    // by default only the in-memory data is reported back

    /api/sessionhistory/ -> list in webdav fashion
    /api/sessionhistory/sessionid?startIndex -> returns full session data
    // delete file with method


    // auto start session? ringbuffer with last n measurements
    //  detect spikes -> more than s spikes -> start session
    // auto stop session if one full chunk is empty