NethVoice CTI: Add recording option to call history filters

[mgarra]

Description

Add a filter in NethVoice CTI call history to easily find calls that have an available recording.

This is especially useful for older calls, where recordings can otherwise be difficult to locate.

Steps to reproduce

1. Open the call history in NethVoice CTI.
2. Open the "Call content" filters.
3. Try to filter calls based on the presence of a recording.

Expected behavior

The "Call content" filter provides an option such as "With recording" to show only calls with an available recording.

Actual behavior

There is no filter to find calls based on the presence of a recording.

See also

• [Support ticket](https://helpdesk.nethesis.it/a/tickets/205752)
• [Mattermost thread](https://mattermost.nethesis.it/nethesis/pl/equewz39piyitkextasouazyoh)
• [NethVoice CTI repository](https://github.com/nethesis/nethvoice-cti)