Define requirement for inclusion

Hi, following https://github.com/fastfetch-cli/fastfetch/pull/2137#issuecomment-3733820379

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What about to set a hard requirement: any new distros that want to add their logo into fastfetch, must have downloadable ISOs and must have a complete webside ( can be simple though )
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I suggest that distros:

* have reached stable state (out of beta, alpha, RC) [NB this is not against rolling distro]
* are still active after 2 years after first reaching stable status
* have a public development for open source distros
* are not private

This to prevent abuse and flexing of being in fastfetch

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I suggest to remove previously added:

* **Furreto Linux** https://github.com/fastfetch-cli/fastfetch/pull/927 still in private beta after more then 2 years, no public develpment, promised to release soon, the discord where it was hosted no longer exist ?

* **EmperorOS** https://github.com/fastfetch-cli/fastfetch/issues/1963 already discontinued, website deleted https://emperoros.github.io/, if download and public development existed they have been deleted, author of Starry Linux which lived for 4 months only, now at the third distro with NurOS-Linux

* **Magix** https://github.com/fastfetch-cli/fastfetch/pull/1228 don't publish an iso image, completely depends on Gento stage3 and users need to build it https://github.com/Magix-OS/stage-gen

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My opinion on some pending

* **Metal OS** https://github.com/fastfetch-cli/fastfetch/pull/2208 https://github.com/fastfetch-cli/fastfetch/issues/2209 A collection of 10 makefiles (https://codeberg.org/DAFT-8/METALOS) between programs and linux-firmware, don't publish an iso; useers need to build it, don't have a compiler or online repositories

* **kyonlinux** https://github.com/fastfetch-cli/fastfetch/issues/2459 no download, no public development

* **miOS** https://github.com/fastfetch-cli/fastfetch/issues/2408 a remix created with cubic; in practice no public development; depends on a single person to put out their backup of an installation

* **CookieOS** https://github.com/fastfetch-cli/fastfetch/issues/2373 there is a download but no public development; their github is empty https://github.com/GAJA-Team/CookieOS , generically says to be open source but there is no proof of it

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Example of a distro with a public development

* https://distroware.gitlab.io/os/Linux/a/arch-linux/#development
* https://distroware.gitlab.io/os/Linux/a/arch-linux/#build

Everybody can see the whole development of the programs, of the packages and easily build the iso locally