add app description

[rosbeef]

added description file :
Phanpy is ans alternative frontend for Mastodon or Gotosocial server which are alternatives to twitter or X.

[xmgz]

sure! thank you, sometimes I forget barely anybody knows Fedierve exist (outside our bubble)

should we be that specific? I mean, wouldn't it be just enough

Phanpy is an alternative frontend for Mastodon and other Fediverse servers which are alternatives to X

I wouldn't even mention X, btw.

But yes, description is too much minimalistic

[rosbeef]

I would add description because this app is not easily searchable in the ynh app catalog.
My main goal is to give a way for people who install gotosocial to find the app and be able to install a selfhosted frontend.
you can remove twitter yes, i don't know if it's right to make a ad to gotosocial but gotosocial (in ynh ecosistem) need phanpy as no other alternative is available.

i just don't realy know how search field works in the app catalog of the web admin. But i imagine it search in the description.md file.

[rosbeef]

It seems that description file is not used by the catalog to search in.

So i have made a PR directly in the core catalogue app file.
YunoHost/apps#2771