Backport #27231 #27259 manually

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Co-authored-by: delvh <dev.lh@web.de>

Follow #23854

Major changes:

1. The old `<div class="ui"><div class="six wide column ...">
</div></div>` doesn't have affect any more
    * So clean them, and remove other unnecessary elements/styles.
2. Add padding for narrow view.

Before

![image](https://user-images.githubusercontent.com/2114189/229262177-e8cf6c9b-b17b-482c-83fe-a84579e01e8e.png)

After:

![image](https://user-images.githubusercontent.com/2114189/229262166-d46134b0-2117-4d5c-a469-a2115cbd4b6c.png)

Before:
<img width="1272" alt="Screenshot 2023-03-31 at 19 56 16"
src="https://user-images.githubusercontent.com/115237/229195611-4570453c-26bf-4663-865b-7e7eb9115060.png">

After:
<img width="1270" alt="Screenshot 2023-03-31 at 20 00 14"
src="https://user-images.githubusercontent.com/115237/229195639-23841b62-38d8-4e43-8ee5-3f70cba5de6e.png">

HTML is not XML.

* Add main aria landmark to templates
 * Adjust some titles to improve understanding of location in navigation

Contributed by @Forgejo

add `alt` for logo in home page

* Refactor `i18n` to `locale`

- Currently we're using the `i18n` variable naming for the `locale`
struct. This contains locale's specific information and cannot be used
for general i18n purpose, therefore refactoring it to `locale` makes
more sense.
- Ref: https://github.com/go-gitea/gitea/pull/20096#discussion_r906699200

* Update routers/install/install.go

Use a new name for this template/frontend variable to make it distinct
from the server variable StaticURLPrefix.

* Consolidate Logos and update README header

- Remove unused `logo-lg.png`, `logo-sm.png` and `logo-192.png`.
- Consolidate `favicon.svg` and `logo.svg` to just `logo.svg`.
- Remove Safari Mask icon, it seems to work fine with just `favicon.png` (no SVG support).
- Remove Fluid Icon. It only served Firefox and SVG works just fine there.
- Update customization instructions.
- Update README.md to use SVG icon, increase logo size and center it and badges.

* Update README_ZH.md

Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>

* Update README_ZH.md

Co-authored-by: 6543 <6543@obermui.de>
Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>
Co-authored-by: techknowlogick <techknowlogick@gitea.io>

* gitea png to logo.svg

* gitea safari svg to logo

* minify svgs

* Update english docs

* Update missing section on customizing logo

* Add class to page content to unify top margin

Previously pages would individually set this margin but some didn't so
content would stick to the header without any space. Resolve this by
adding a new class that is added on all pages. The only place where we
remove this margin again is on the pages with menu or wrapper in the
header.

* fix admin notices

* fix team pages

* fix loading segment on gitgraph for arc-green

* fix last missing case

Co-authored-by: techknowlogick <techknowlogick@gitea.io>

Now defaults to 16 on both frontend and backend.

Co-authored-by: techknowlogick <techknowlogick@gitea.io>

* Add octicon SVG sprite

Signed-off-by: jolheiser <john.olheiser@gmail.com>

* Static prefix

Signed-off-by: jolheiser <john.olheiser@gmail.com>

* SVG for all repo icons

Signed-off-by: jolheiser <john.olheiser@gmail.com>

* make vendor

Signed-off-by: jolheiser <john.olheiser@gmail.com>

* Swap out octicons

Signed-off-by: jolheiser <john.olheiser@gmail.com>

* Move octicons to top of less imports

Signed-off-by: jolheiser <john.olheiser@gmail.com>

* Fix JS

Signed-off-by: jolheiser <john.olheiser@gmail.com>

* Definitely not a search/replace

Signed-off-by: jolheiser <john.olheiser@gmail.com>

* Missed regex

Signed-off-by: jolheiser <john.olheiser@gmail.com>

* Move to more generic calls and webpack

Signed-off-by: jolheiser <john.olheiser@gmail.com>

* make svg -> make webpack

Signed-off-by: jolheiser <john.olheiser@gmail.com>

* Remove svg-sprite

Signed-off-by: jolheiser <john.olheiser@gmail.com>

* Update tests

Signed-off-by: jolheiser <john.olheiser@gmail.com>

* Missed a test

Signed-off-by: jolheiser <john.olheiser@gmail.com>

* Remove svg from makefile

Signed-off-by: jolheiser <john.olheiser@gmail.com>

* Suggestions

Signed-off-by: jolheiser <john.olheiser@gmail.com>

* Attempt to fix test

Signed-off-by: jolheiser <john.olheiser@gmail.com>

* Update tests

Signed-off-by: jolheiser <john.olheiser@gmail.com>

* Revert timetracking test

Signed-off-by: jolheiser <john.olheiser@gmail.com>

* Swap .octicon for .svg in less

Signed-off-by: jolheiser <john.olheiser@gmail.com>

* Add aria-hidden

Signed-off-by: jolheiser <john.olheiser@gmail.com>

* Replace mega-octicon

Signed-off-by: jolheiser <john.olheiser@gmail.com>

* Fix webpack globbing on Windows

Signed-off-by: jolheiser <john.olheiser@gmail.com>

* Revert

Co-Authored-By: silverwind <me@silverwind.io>

* Fix octions from upstream

Signed-off-by: jolheiser <john.olheiser@gmail.com>

* Fix Vue and missed JS function

Signed-off-by: jolheiser <john.olheiser@gmail.com>

* Add JS helper and PWA

Signed-off-by: jolheiser <john.olheiser@gmail.com>

* Preload SVG

Signed-off-by: jolheiser <john.olheiser@gmail.com>

Co-authored-by: silverwind <me@silverwind.io>
Co-authored-by: techknowlogick <matti@mdranta.net>

* static url

* add cors support for static resources

* [assets] work on the migration to configurable url for assets

Signed-off-by: Jakob Ackermann <das7pad@outlook.com>

* [misc] fix whitespace

Signed-off-by: Jakob Ackermann <das7pad@outlook.com>

* [assets] fix the loading of the manifest.json

It is generated dynamically, and as such can not be served by the cdn.

Signed-off-by: Jakob Ackermann <das7pad@outlook.com>

* Revert "add cors support for static resources"

This reverts commit 42f964fd18

Signed-off-by: Jakob Ackermann <das7pad@outlook.com>

* [docs] add the STATIC_URL_PREFIX option

Signed-off-by: Jakob Ackermann <das7pad@outlook.com>

* [docs] reverse-proxy: nginx: add two setups for STATIC_URL_PREFIX

Signed-off-by: Jakob Ackermann <das7pad@outlook.com>

* [assets] migrate the url of a new asset to the static url prefix

REF: f2a3abc683
Signed-off-by: Jakob Ackermann <das7pad@outlook.com>

I'm a native speaker, it looks much better this way

It was just missing

NOTE: this commit only updates the english section

Signed-off-by: Jan Breuer <jan.breuer@jaybee.cz>

Commit 7bb4d610e5 tries to take the app_name from the locale, however, it is a user defined setting. This causes the app name to simply display as `app_name` instead of the correct value.

templates/helper.go automatically injects the AppName variable into every template, so we can safely use that instead.

Signed-off-by: Daniel Derzsi <daniel@tohka.us>

Would it make sense to actually use the configured app name on the home page?

.. rather than a gogs one

* fix homepage docs link broken

* fix homepage docs links after docs updated

* Added rel="noopener" to target="_blank" hrefs

* Replaced gogs.io/docs with docs.gitea.io

This commit improves templates readability, since all of them use consistent
indent with all template command blocks indented too.

1. Indents both HTML containers such as <div>, <p> and Go HTML template blocks
   such as {{if}} {{with}}

2. Cleans all trailing white-space

3. Adds trailing last line-break to each file

Conflicts:
	modules/setting/setting.go

Conflicts:
	templates/repo/release/list.tmpl
	templates/user/dashboard/dashboard.tmpl

Conflicts:
	routers/repo/setting.go

Removed trailing whitespaces with

```sh
for file in `grep -r " $" * | cut -d : -f 1 | sort | uniq | grep -v " "`; do sed -i 's/[ \t]*$//' $file; done
```

and some handwork.