Migrate to Vite+ unified toolchain (#428)

.vscode/extensions.json

@@ -1,3 +1,3 @@
 {
-  "recommendations": ["biomejs.biome", "rust-lang.rust-analyzer", "bradlc.vscode-tailwindcss"]
+  "recommendations": ["rust-lang.rust-analyzer", "bradlc.vscode-tailwindcss", "VoidZero.vite-plus-extension-pack"]
 }

.vscode/settings.json

@@ -1,6 +1,8 @@
 {
-  "editor.defaultFormatter": "biomejs.biome",
+  "editor.defaultFormatter": "oxc.oxc-vscode",
   "editor.formatOnSave": true,
-  "biome.enabled": true,
-  "biome.lint.format.enable": true
+  "editor.formatOnSaveMode": "file",
+  "editor.codeActionsOnSave": {
+    "source.fixAll.oxc": "explicit"
+  }
 }