[feature] Show a summary which packages exist for major distros

[yurivict]

Currently, when the user looks at the list he can't immediately tell which packages are or aren't available. Ex. https://repology.org/project/emscripten/versions It is necessary to go through the long list, or perform textual search.

I suggest that you add the summary box in the top-right corner with the summary/aggregate information at a glance, ex:

Debian    yes (for some, ex. Ubuntu 18, etc.)
Fedora    no
Arch      yes
Slack     no
Gentoo    no
MacOS     no
FreeBSD   yes

This should be with one line for every unique packaging system, with details when many distros use the same packaging system.

I often find myself hitting Ctrl-C and typing "freebsd" to find if it is available for freebsd, etc.

This is a usability feature, it adds user convenience, and not information that wasn't previously available.

[AMDmi3]

At first glance, it's data duplication. But it actually related to other things planned repology/repology-webapp#44, repology/repology-updater#562, repology/repology-updater#514 and probably more. I'm not sure how to it in an usable way yet though.

This should be with one line for every unique packaging system, with details when many distros use the same packaging system.

This won't be much different from the Versions page, as there's still a lot of families (242 repos, 66 families currently), so you'll still have to scroll a lot, and if you need details about specific repository, you'll need to scroll even more. repology/repology-webapp#44 should help somewhat, especially when there's a lot of packages (e.g. language packs).

[AMDmi3]

The rough idea is as follows: a multi-column (so it doesn't take too much vertical space) list (similar to Absent in repositories at the bottom of Versions page) with repository families the project is packaged in. Entries would be clickable, highlighting table rows for all repositories belonging to the selected family, and scrolling to the first (or main, but we'll have to set this by hand) representative of the family (e.g. Arch (and not Manjaro) for Arch family). How does that sound?

This is also somewhat related to repology/repology-webapp#37.

[XVilka]

@AMDmi3 condensing into repository families indeed sounds like a good solution! 👍

Also related: #102