fix(details): trim newlines at the beginning and end of code during rendering

Author: WarningImHack3r

src/routes/[pid=pid]/[org]/[repo]/[id=number]/PageRenderer.svelte

@@ -59,15 +59,19 @@
 	import Step from "$lib/components/Step.svelte";
 	import Steps from "$lib/components/Steps.svelte";
 	import BottomCollapsible from "./BottomCollapsible.svelte";
-	import { transformerDiffMarking, transformerLanguageDetection } from "./syntax-highlighting";
+	import {
+		transformerDiffMarking,
+		transformerLanguageDetection,
+		transformerTrimCode
+	} from "./syntax-highlighting";
 
 	const shikiPlugin: Plugin = {
 		rehypePlugin: [
 			rehypeShikiFromHighlighter,
 			highlighter,
 			{
 				themes: { light: "github-light-default", dark: "github-dark-default" },
-				transformers: [transformerLanguageDetection, transformerDiffMarking]
+				transformers: [transformerTrimCode, transformerLanguageDetection, transformerDiffMarking]
 			} satisfies Parameters<typeof rehypeShikiFromHighlighter>[1]
 		]
 	};

src/routes/[pid=pid]/[org]/[repo]/[id=number]/syntax-highlighting.ts

@@ -25,6 +25,15 @@ export function detectLanguage(code: string): (SpecialLanguage | (string & {}))
 	if (/[a-z-]+: \S+/.test(code)) return "css";
 }
 
+/**
+ * A transformer that trims unnecessary whitespace at the beginning and end of the string.
+ */
+export const transformerTrimCode: ShikiTransformer = {
+	preprocess(code) {
+		return code.replace(/(^\r?\n|\r?\n$)/g, "");
+	}
+};
+
 /**
  * A Shiki transformer used for language detection and setting the appropriate language metadata
  * in code blocks. Useful for handling code snippets with "diff" language and converting them