Signed-off-by: Andrew Thornton <art27@cantab.net>

Make sure to end up with the same syntax highlighting inside various sections of diffs by processing the code first before detecting specific changes between the lines. Also try and make sure that when highlighting individual lines in a diff that it is tokenized the same as it would be when part of an entire file with more context.

Fixes: #12190

* Make copy/paste work for source code

Fix regression casued by #12047 so copy/paste works properly in all browsers.

Fixes #12184

Also while looking at this I saw a small display issue for blame view. I think #12023 was merged into original PR through an update branch before #12047 was merged and made one of the css ruules not apply anymore.

* use pseudo-element to prevent copying of comment + symbol even when not visually selected

* remove added newline here should not be necessary anymore

* make sure empty line is newline so there is something to select and copy

* Remove newline when highlighting random chunks of code

Somewhere when tokenizing a newline gets added to code formatted by chroma. This breaks the case of 'added-code' inside of an 'added-line' in a diff. Just remove any newline when processing chunks of code since we don't need it.

Fixes #12172

* don't process empty lines

* This is the proper way to fix this by telling chroma not to add the newline in the first place

* Server-side syntax hilighting for all code

This PR does a few things:

* Remove all traces of highlight.js
* Use chroma library to provide fast syntax hilighting directly on the server
* Provide syntax hilighting for diffs
* Re-style both unified and split diffs views
* Add custom syntax hilighting styling for both regular and arc-green

Fixes #7729
Fixes #10157
Fixes #11825
Fixes #7728
Fixes #3872
Fixes #3682

And perhaps gets closer to #9553

* fix line marker

* fix repo search

* Fix single line select

* properly load settings

* npm uninstall highlight.js

* review suggestion

* code review

* forgot to call function

* fix test

* Apply suggestions from code review

suggestions from @silverwind thanks

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

* code review

* copy/paste error

* Use const for highlight size limit

* Update web_src/less/_repository.less

Co-authored-by: Lauris BH <lauris@nix.lv>

* update size limit to 1MB and other styling tweaks

* fix highlighting for certain diff sections

* fix test

* add worker back as suggested

Co-authored-by: silverwind <me@silverwind.io>
Co-authored-by: Lauris BH <lauris@nix.lv>

Data partially based on [CodeMirror's meta.js](https://github.com/codemirror/CodeMirror/blob/master/mode/meta.js).

Fixes: https://github.com/go-gitea/gitea/issues/6057

* Fix specific highlighting.

* Highlighting CMakeLists.txt:
remove case sensitive checks.
use lowercase checks instead.

* Update HighlightJS to 9.11.0

* Fix YAML files highlighting

Integrated optional bindata for the templates