[IMPROVE] Expand the feature set of the new message rendering (Rocket…

…Chat#25970)

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## Proposed changes (including videos or screenshots)
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- Everything inside a new package (`@rocket.chat/gazzodown`);
- KaTeX support;
- Highlighted Words support;
- Emoji rendering expanded;
- Code rendering fixed
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## Issue(s)
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## Steps to test or reproduce
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_templates/package/new/package.json.ejs.t

@@ -18,7 +18,7 @@ to: packages/<%= name %>/package.json
 		"lint:fix": "eslint --ext .js,.jsx,.ts,.tsx . --fix",
 		"jest": "jest",
 		"build": "rm -rf dist && tsc -p tsconfig.json",
-		"dev": "tsc -p --watch --preserveWatchOutput tsconfig.json"
+		"dev": "tsc -p tsconfig.json --watch --preserveWatchOutput"
 	},
 	"main": "./dist/index.js",
 	"typings": "./dist/index.d.ts",

apps/meteor/app/theme/client/imports/general/base_old.css

@@ -2934,6 +2934,8 @@
 .rc-old .highlight-text {
 	padding: 2px;
 
+	color: inherit;
+
 	border-radius: 15px;
 	background-color: var(--selection-background);
 }