Extend https://github.com/go-gitea/gitea/pull/21432 to commit messages.
Color is changed because the markup code block bg does not offer enough
contrast on varying backgrounds.

<img width="568" alt="Screenshot 2024-03-27 at 19 52 55"
src="https://github.com/go-gitea/gitea/assets/115237/ddc9307e-f32f-4e97-8b88-91f88ced2a36">
<img width="573" alt="Screenshot 2024-03-27 at 19 53 33"
src="https://github.com/go-gitea/gitea/assets/115237/14b30fd2-bf28-46b8-9e82-eb60a28f6bf2">
<img width="422" alt="Screenshot 2024-03-27 at 19 53 01"
src="https://github.com/go-gitea/gitea/assets/115237/a12136b5-c02b-460c-9830-f830542987ae">
<img width="397" alt="Screenshot 2024-03-27 at 19 53 27"
src="https://github.com/go-gitea/gitea/assets/115237/c9f05d81-c73e-468e-98e9-e5929bc0da3e">
<img width="333" alt="Screenshot 2024-03-27 at 19 53 07"
src="https://github.com/go-gitea/gitea/assets/115237/06b5a9f9-f95d-46b6-8c57-df0b02555652">
<img width="279" alt="Screenshot 2024-03-27 at 19 53 21"
src="https://github.com/go-gitea/gitea/assets/115237/b06a0afc-ddd8-48ae-b557-a6dc47802e68">

just some missed nits

the issue is, that you can not distinguish between normal and archived
labels.

So this will make archived labels 80% **grayscale**. And prepend
"Archived: " to the tooltip info


![image](https://github.com/go-gitea/gitea/assets/24977596/fd77c4d2-eff5-4afd-9bfa-19cb9991c5e7)

![image](https://github.com/go-gitea/gitea/assets/24977596/2e0f30e5-f301-4c9c-8e9f-677298d90b27)

![image](https://github.com/go-gitea/gitea/assets/24977596/53d70abf-b306-453d-aa95-a3a035b19a33)

![image](https://github.com/go-gitea/gitea/assets/24977596/6020e5f5-2364-4807-979f-37dffa8735e5)


---
*Sponsored by Kithara Software GmbH*

---------

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

This PR touches the most interesting part of the "template refactoring".

1. Unclear variable type. Especially for "web/feed/convert.go":
sometimes it uses text, sometimes it uses HTML.
2. Assign text content to "RenderedContent" field, for example: `
project.RenderedContent = project.Description` in web/org/projects.go
3. Assign rendered content to text field, for example: `r.Note =
rendered content` in web/repo/release.go
4. (possible) Incorrectly calling `{{Str2html
.PackageDescriptor.Metadata.ReleaseNotes}}` in
package/content/nuget.tmpl, I guess the name Str2html misleads
developers to use it to "render string to html", but it only sanitizes.
if ReleaseNotes really contains HTML, then this is not a problem.

Fixes #26548

This PR refactors the rendering of markup links. The old code uses
`strings.Replace` to change some urls while the new code uses more
context to decide which link should be generated.

The added tests should ensure the same output for the old and new
behaviour (besides the bug).

We may need to refactor the rendering a bit more to make it clear how
the different helper methods render the input string. There are lots of
options (resolve links / images / mentions / git hashes / emojis / ...)
but you don't really know what helper uses which options. For example,
we currently support images in the user description which should not be
allowed I think:

<details>
  <summary>Profile</summary> 

https://try.gitea.io/KN4CK3R

![grafik](https://github.com/go-gitea/gitea/assets/1666336/109ae422-496d-4200-b52e-b3a528f553e5)

</details>

---------

Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

Follow GitHubs behavior of showing the label description as a tooltip
instead of the browser native title.

## Before

![grafik](https://github.com/go-gitea/gitea/assets/51889757/70448327-467b-4bee-b799-40a442a5ce16)


## After

![grafik](https://github.com/go-gitea/gitea/assets/51889757/abe7d700-148b-4cef-a487-6b0f8f20b212)

Co-authored-by: Gusted <postmaster@gusted.xyz>

- The label HTML contained a quote that wasn't being closed.

Refs: https://codeberg.org/forgejo/forgejo/pulls/1651

(cherry picked from commit e2bc2c9a1f)

Co-authored-by: Gusted <postmaster@gusted.xyz>

Backtick syntax now works in repo description too. Also, I replaced the
CSS for this was a new single class, making it more flexible and not
dependent on a parent. Also, very slightly reduced font size from 16.8px
to 16px.

---------

Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

Commit with `echo "\nmessage after a blank line\nsecond line of the
message" | git commit --cleanup=verbatim -F -` and push.

<img width="1139" alt="image"
src="https://github.com/go-gitea/gitea/assets/9418365/f9a2c28c-e307-4c78-9e31-3d3ace7b9274">

Close #24508

Main changes:
As discussed in the issue

1. Change luminance calculation function to use [Relative
Luminance](https://www.w3.org/WAI/GL/wiki/Relative_luminance)
2. Move the luminance related functions into color.go/color.js
3. Add tests for both the files (Not sure if test cases are too many
now)

Before (tests included by `UseLightTextOnBackground` are labels started
with `##`):
https://try.gitea.io/HesterG/testrepo/labels

After:
<img width="1307" alt="Screen Shot 2023-05-08 at 13 37 55"
src="https://user-images.githubusercontent.com/17645053/236742562-fdfc3a4d-2fab-466b-9613-96f2bf96b4bc.png">
<img width="1289" alt="Screen Shot 2023-05-08 at 13 38 06"
src="https://user-images.githubusercontent.com/17645053/236742570-022db68e-cec0-43bb-888a-fc54f5332cc3.png">
<img width="1299" alt="Screen Shot 2023-05-08 at 13 38 20"
src="https://user-images.githubusercontent.com/17645053/236742572-9af1de45-fb7f-460b-828d-ba25fae20f51.png">

---------

Co-authored-by: silverwind <me@silverwind.io>
Co-authored-by: Giteabot <teabot@gitea.io>

It seems that we really need the "context function" soon. So we should
clean up the helper functions first.

Major changes:

* Improve StringUtils and add JsonUtils
* Remove one-time-use helper functions like CompareLink
* Move other code (no change) to util_avatar/util_render/util_misc (no
need to propose changes for them)

I have tested the changed templates:


![image](https://user-images.githubusercontent.com/2114189/235283862-608dbf6b-2da3-4d06-8157-b523ca93edb4.png)


![image](https://user-images.githubusercontent.com/2114189/235283888-1dfc0471-e622-4d64-9d76-7859819580d3.png)


![image](https://user-images.githubusercontent.com/2114189/235283903-d559f14d-4abb-4a50-915f-2b9cbc381a7a.png)


![image](https://user-images.githubusercontent.com/2114189/235283955-b7b5adea-aca3-4758-b38a-3aae3f7c6048.png)

---------

Co-authored-by: Giteabot <teabot@gitea.io>