Max video duration hour options does not display different video length

[ldfsilva]

Describe the bug
The max video duration hour options (1, 4, 24, infinite) does not display different video length segments in the playback UI, despite the selection the video segments remain the same.

To Reproduce
Steps to reproduce the behavior:

1. Go to 'Moonfire UI'
2. Click on 'Login'
3. Select either 'Main' or 'Sub' streams
4. Select a date that have recordings
5. Choose the 'Max video duration' of choice (either of 1, 4, 24 or infinite hours)
6. See the error, despite the selection the displayed 'start' and 'end' video segment on the right panel remains the same

Expected behavior
The video segments displayed to reflect the chosen 'Max video duration' length accordingly, either of the hour options offered (1, 4, 24 or infinite).

Note in screenshot example (screenshots/list.png) shows it used to work, given the selection is set to 1 hours and the video segments have 1 hour duration.

Screenshots
See below screenshots for 1 and 4 hours selection, note that despite selection the video segments are all 5 minutes apart from each other.

1 hour

4 hours

Server (please complete the following information):

• moonfire-nvr --version

[moonfire-nvr@nuc sample]$ moonfire-nvr --version
Version: v0.7.8

Camera (please complete the following information):

• Amcrest IP2M-841

Desktop (please complete the following information):

• Browser [e.g. chrome, safari];
  • Firefox 117.0 (64-bit)
  • Chrome 119.0.6045.159 (Official Build) (x86_64)

Additional context
The behavior is the same if I try from mobile (Chrome and DuckDuckGo browsers), so it doesn't seem to be a browser issue. Here's 100 most recent recordings entries from the following, can provide additional data if that'd help better understand state of recordings.

sudo -u moonfire-nvr moonfire-nvr sql "select * from recording order by start_time_90k desc limit 100" 

https://gist.github.com/ldfsilva/4bb33f4d02f9f0e009ca7c16bb87a60f

[ldfsilva]

An example exposing the duration with this patch master...ldfsilva:moonfire-nvr:add_duration, I wonder if this is led by non-contiguous video samples, which upon closer look to screenshots/list.png also had same behavior (eg; 12:48:31 - 12:53:25).