[4.x]: Customize sources lacks setting for section type

What happened?

Description

Due to the new way of creating globals, categories etc it would be great to see an source option for section type (Single, Structure, Channel). When entrifying a global set it becomes a single section. WIthin the Entries > singles there is now a cluttered overview with entries lacking urls (because they don't have them) and the actual single pages.

When adding a new custom source there is no option to only view single sections. This would resolve this issue. But maybe it's also an idea to add the filter to the singles source, display only when URL is set.

Steps to reproduce

1. Add a single section (eg. contact)
2. Add a single section for global use (no URL set)

Expected behavior

The single source within the Entries tab to filter out the globals for clarity in the overview.

Actual behavior

Everything is presented within the Single source. Custom sources are possible but with big sites containing a lot of sections, you need to manually add them to the source filter.

Craft CMS version

4.4.16.1

PHP version

8.2.8

Operating system and version

macOS Ventura 13.5 (22G74)

Database type and version

MariaDB 10.4.30

Image driver and version

Imagick 3.7.0

Installed plugins and versions

N/A

Start in the Entries tab and inspect how custom sources and the Singles source define their filters. Trace how section types and URLs are represented for single sections, then verify that a source can distinguish regular singles from globals and that the Entries overview shows only the intended sections.