fix: pre-bundle xterm packages to resolve MIME type error in terminal

Vite's dev server was returning HTML error pages instead of JS for
dynamically imported @xterm/* modules, causing 'text/html is not a
valid JavaScript MIME type' failures during terminal initialization.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

packages/dashboard/vite.config.ts

@@ -10,6 +10,14 @@ export default defineConfig({
       "@fusion/core": resolve(__dirname, "../core/src/types.ts"),
     },
   },
+  optimizeDeps: {
+    include: [
+      "@xterm/xterm",
+      "@xterm/addon-fit",
+      "@xterm/addon-web-links",
+      "@xterm/addon-webgl",
+    ],
+  },
   build: {
     outDir: "../dist/client",
     emptyOutDir: true,