This is a PR for #3616
Currently added a new optional config `SLOGAN` in ini file. When this config is set title page is modified in APP_NAME [ - SLOGAN]
Example in image below
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Add the new config value in the admin settings page (readonly)
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## TODO
* [x] Add the possibility to add the `SLOGAN` config from the installation form
* [ ] Update https://forgejo.org/docs/next/admin/config-cheat-sheet
Reviewed-on: https://codeberg.org/forgejo/forgejo/pulls/3752
Reviewed-by: 0ko <0ko@noreply.codeberg.org>
Reviewed-by: Earl Warren <earl-warren@noreply.codeberg.org>
Co-authored-by: mirko <mirko.perillo@gmail.com>
Co-committed-by: mirko <mirko.perillo@gmail.com>