Incomplete segmentation lost useful vessel trajectory information

[tsuzzy]

Description
The segmentation function split_timedelta, in combination with _splits_idx and _segment_rng, produce incomplete segments when processing AIS data. This issue potentially removes useful vessel information from the segmented tracks, leaving the incomplete visualization of vessel movements.

Sample code to reproduce the issue

MMSI = 636018124

# Set the start and end times for the query
start_time = datetime.strptime("2018-01-01 00:00:00", '%Y-%m-%d %H:%M:%S')
end_time = datetime.strptime("2018-01-31 00:00:00", '%Y-%m-%d %H:%M:%S')

with aisdb.SQLiteDBConn(dbpath=dbpath) as dbconn:
    qry = aisdb.DBQuery(
        dbconn=dbconn,
        dbpath='./data/meridian_2018_vacuumed.db',
        start=start_time,
        end=end_time,
        mmsi = MMSI,
        callback=aisdb.database.sqlfcn_callbacks.in_timerange_hasmmsi,
    )
    rowgen = qry.gen_qry()
    tracks = aisdb.track_gen.TrackGen(rowgen, decimate=False)
    
    # Split the tracks into segments based on the maximum time interval
    track_segments = aisdb.split_timedelta(tracks, timedelta(hours=24))
    
    aisdb.web_interface.visualize(
        track_segments,
        domain=domain,
        visualearth=True,
        open_browser=True,
    )

Before segmentation:

After segmentation with 24 hours as the max time interval:

Expected output is for the trajectory to be split into multiple single-voyage track segments. However, the actual output may only contain partial segments of these expected trajectories.