Migration to Nuxt v4 file structure and dependencies update

app/composables/useMarkdown.ts

@@ -0,0 +1,58 @@
+import { unified, type Processor } from "unified";
+import type { Root } from 'hast';
+import RemarkParse from "remark-parse";
+
+import RemarkRehype from 'remark-rehype';
+import RemarkOfm from 'remark-ofm';
+import RemarkGfm from 'remark-gfm';
+import RemarkBreaks from 'remark-breaks';
+import RemarkFrontmatter from 'remark-frontmatter';
+import StripMarkdown from 'strip-markdown';
+import RemarkStringify from 'remark-stringify';
+
+interface Parser
+{
+    parse: (md: string) => Promise<Root>;
+    parseSync: (md: string) => Root;
+    text: (md: string) => string;
+}
+export default function useMarkdown(): Parser
+{
+    let processor: Processor, processorSync: Processor;
+
+    const parse = (markdown: string) => {
+        if (!processor) 
+        {
+            processor = unified().use([RemarkParse, RemarkGfm, RemarkOfm, RemarkBreaks, RemarkFrontmatter]);
+            processor.use(RemarkRehype);
+        }
+
+        const processed = processor.run(processor.parse(markdown)) as Promise<Root>;
+        return processed;
+    }
+
+    const parseSync = (markdown: string) => {
+        if (!processor) 
+        {
+            processor = unified().use([RemarkParse, RemarkGfm, RemarkOfm, RemarkBreaks, RemarkFrontmatter]);
+            processor.use(RemarkRehype);
+        }
+
+        const processed = processor.runSync(processor.parse(markdown)) as Root;
+        return processed;
+    }
+
+    const text = (markdown: string) => {
+        if (!processor) 
+        {
+            processor = unified().use([RemarkParse, RemarkGfm, RemarkOfm, RemarkBreaks, RemarkFrontmatter ]);
+            processor.use(StripMarkdown, { remove: [ 'comment', 'tag', 'callout' ] });
+            processor.use(RemarkStringify);
+        }
+
+        const processed = processor.processSync(markdown);
+        return String(processed);
+    }
+
+    return { parse, parseSync, text };
+}