Add experimental support for SolidStart to Vite plugin (#825)

Author: markdalgleish

.changeset/chilled-pets-help.md

@@ -0,0 +1,5 @@
+---
+'@vanilla-extract/vite-plugin': minor
+---
+
+Add experimental support for [SolidStart](https://github.com/solidjs/solid-start)

packages/vite-plugin/src/index.ts

@@ -68,7 +68,11 @@ export function vanillaExtractPlugin({
         postCssConfig = await resolvePostcssConfig(config);
       }
 
-      if (config.plugins.some((p) => p.name === 'astro:build')) {
+      if (
+        config.plugins.some((plugin) =>
+          ['astro:build', 'solid-start-server'].includes(plugin.name),
+        )
+      ) {
         forceEmitCssInSsrBuild = true;
       }
     },