Server-side syntax highlighting for all code (#12047)

* 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>

vendor/github.com/alecthomas/chroma/lexers/c/cql.go

@@ -0,0 +1,69 @@
+package c
+
+import (
+	. "github.com/alecthomas/chroma" // nolint
+	"github.com/alecthomas/chroma/lexers/internal"
+)
+
+// CassandraCQL lexer.
+var CassandraCQL = internal.Register(MustNewLexer(
+	&Config{
+		Name:            "Cassandra CQL",
+		Aliases:         []string{"cassandra", "cql"},
+		Filenames:       []string{"*.cql"},
+		MimeTypes:       []string{"text/x-cql"},
+		NotMultiline:    true,
+		CaseInsensitive: true,
+	},
+	Rules{
+		"root": {
+			{`\s+`, TextWhitespace, nil},
+			{`(--|\/\/).*\n?`, CommentSingle, nil},
+			{`/\*`, CommentMultiline, Push("multiline-comments")},
+			{`(ascii|bigint|blob|boolean|counter|date|decimal|double|float|frozen|inet|int|list|map|set|smallint|text|time|timestamp|timeuuid|tinyint|tuple|uuid|varchar|varint)\b`, NameBuiltin, nil},
+			{Words(``, `\b`, `ADD`, `AGGREGATE`, `ALL`, `ALLOW`, `ALTER`, `AND`, `ANY`, `APPLY`, `AS`, `ASC`, `AUTHORIZE`, `BATCH`, `BEGIN`, `BY`, `CLUSTERING`, `COLUMNFAMILY`, `COMPACT`, `CONSISTENCY`, `COUNT`, `CREATE`, `CUSTOM`, `DELETE`, `DESC`, `DISTINCT`, `DROP`, `EACH_QUORUM`, `ENTRIES`, `EXISTS`, `FILTERING`, `FROM`, `FULL`, `GRANT`, `IF`, `IN`, `INDEX`, `INFINITY`, `INSERT`, `INTO`, `KEY`, `KEYS`, `KEYSPACE`, `KEYSPACES`, `LEVEL`, `LIMIT`, `LOCAL_ONE`, `LOCAL_QUORUM`, `MATERIALIZED`, `MODIFY`, `NAN`, `NORECURSIVE`, `NOSUPERUSER`, `NOT`, `OF`, `ON`, `ONE`, `ORDER`, `PARTITION`, `PASSWORD`, `PER`, `PERMISSION`, `PERMISSIONS`, `PRIMARY`, `QUORUM`, `RENAME`, `REVOKE`, `SCHEMA`, `SELECT`, `STATIC`, `STORAGE`, `SUPERUSER`, `TABLE`, `THREE`, `TO`, `TOKEN`, `TRUNCATE`, `TTL`, `TWO`, `TYPE`, `UNLOGGED`, `UPDATE`, `USE`, `USER`, `USERS`, `USING`, `VALUES`, `VIEW`, `WHERE`, `WITH`, `WRITETIME`, `REPLICATION`, `OR`, `REPLACE`, `FUNCTION`, `CALLED`, `INPUT`, `RETURNS`, `LANGUAGE`, `ROLE`, `ROLES`, `TRIGGER`, `DURABLE_WRITES`, `LOGIN`, `OPTIONS`, `LOGGED`, `SFUNC`, `STYPE`, `FINALFUNC`, `INITCOND`, `IS`, `CONTAINS`, `JSON`, `PAGING`, `OFF`), Keyword, nil},
+			{"[+*/<>=~!@#%^&|`?-]+", Operator, nil},
+			{`(?s)(java|javascript)(\s+)(AS)(\s+)('|\$\$)(.*?)(\5)`,
+				UsingByGroup(
+					internal.Get,
+					1, 6,
+					NameBuiltin, TextWhitespace, Keyword, TextWhitespace,
+					LiteralStringHeredoc, LiteralStringHeredoc, LiteralStringHeredoc,
+				),
+				nil,
+			},
+			{`(true|false|null)\b`, KeywordConstant, nil},
+			{`0x[0-9a-f]+`, LiteralNumberHex, nil},
+			{`[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}`, LiteralNumberHex, nil},
+			{`\.[0-9]+(e[+-]?[0-9]+)?`, Error, nil},
+			{`-?[0-9]+(\.[0-9])?(e[+-]?[0-9]+)?`, LiteralNumberFloat, nil},
+			{`[0-9]+`, LiteralNumberInteger, nil},
+			{`'`, LiteralStringSingle, Push("string")},
+			{`"`, LiteralStringName, Push("quoted-ident")},
+			{`\$\$`, LiteralStringHeredoc, Push("dollar-string")},
+			{`[a-z_]\w*`, Name, nil},
+			{`:(['"]?)[a-z]\w*\b\1`, NameVariable, nil},
+			{`[;:()\[\]\{\},.]`, Punctuation, nil},
+		},
+		"multiline-comments": {
+			{`/\*`, CommentMultiline, Push("multiline-comments")},
+			{`\*/`, CommentMultiline, Pop(1)},
+			{`[^/*]+`, CommentMultiline, nil},
+			{`[/*]`, CommentMultiline, nil},
+		},
+		"string": {
+			{`[^']+`, LiteralStringSingle, nil},
+			{`''`, LiteralStringSingle, nil},
+			{`'`, LiteralStringSingle, Pop(1)},
+		},
+		"quoted-ident": {
+			{`[^"]+`, LiteralStringName, nil},
+			{`""`, LiteralStringName, nil},
+			{`"`, LiteralStringName, Pop(1)},
+		},
+		"dollar-string": {
+			{`[^\$]+`, LiteralStringHeredoc, nil},
+			{`\$\$`, LiteralStringHeredoc, Pop(1)},
+		},
+	},
+))