shikiCodeBlocks: support file preview (#1977)

src/plugins/shikiCodeblocks.desktop/index.ts

@@ -42,6 +42,13 @@ export default definePlugin({
                 match: /codeBlock:\{react\((\i),(\i),(\i)\)\{/,
                 replace: "$&return $self.renderHighlighter($1,$2,$3);"
             }
+        },
+        {
+            find: ".PREVIEW_NUM_LINES",
+            replacement: {
+                match: /(?<=function \i\((\i)\)\{)(?=let\{text:\i,language:)/,
+                replace: "return $self.renderHighlighter({lang:$1.language,content:$1.text});"
+            }
         }
     ],
     start: async () => {