gitea/templates/shared
Denys Konovalov be23b73e85
Restructure issue list template, styles ()
This PR does various modifications on the issue list shared template:
- restructure layout to achieve better responsiveness
-  fix various style issues
- restructure styles (better result with less code :)
- remove numerous `gt-*` patches and other unneeded classes -> use
existing css classes

<details>
<summary>Before:</summary>

![Bildschirmfoto vom 2023-07-07
14-35-00](https://github.com/go-gitea/gitea/assets/47871822/5301fc80-d58b-41c2-8090-5867e2e8459c)
![Bildschirmfoto vom 2023-07-07
14-35-19](https://github.com/go-gitea/gitea/assets/47871822/d36ab691-7dc4-44bb-a8f6-a4105a2a6777)
![Bildschirmfoto vom 2023-07-07
14-35-43](https://github.com/go-gitea/gitea/assets/47871822/0762c852-eb40-4b00-8757-c5dbfd2ae569)
</details>

<details>
<summary>After:</summary>

![Bildschirmfoto vom 2023-07-07
14-32-04](https://github.com/go-gitea/gitea/assets/47871822/0ac42d36-f98f-451a-b556-70c913d19df8)
![Bildschirmfoto vom 2023-07-07
14-31-32](https://github.com/go-gitea/gitea/assets/47871822/520fac9c-33e3-4290-bfe1-6e941f1100f8)
![Bildschirmfoto vom 2023-07-07
14-31-14](https://github.com/go-gitea/gitea/assets/47871822/05ad46bb-3c67-403d-85b8-d12d64f99c59)

</details>

---------

Co-authored-by: silverwind <me@silverwind.io>
..
actions use css on labels ()
secrets Support configuration variables on Gitea Actions ()
user Following up fixes for "Fix inconsistent user profile layout across tabs" ()
variables Support configuration variables on Gitea Actions ()
combomarkdowneditor.tmpl Several fixes for mobile UI ()
issueicon.tmpl Rework notifications list ()
issuelist.tmpl Restructure issue list template, styles ()
searchbottom.tmpl Move helpers to be prefixed with `gt-` ()
searchinput.tmpl Introduce shared template for search inputs ()