vite.config.mts: update css output name

I missed this when updating deps I guess, but the default output is now
main.css... so we need to transform that into styles.css otherwise
Obsidian does not pick it up!

Author: jamiebrynes7

plugin/vite.config.mts

@@ -59,7 +59,7 @@ export default defineConfig({
       external: ["obsidian"],
       output: {
         assetFileNames: (assetInfo) => {
-          if (assetInfo.name === "style.css") {
+          if (assetInfo.name === "main.css") {
             return "styles.css";
           }