Bump to v0.18.0 (#1026)

<!-- This is an auto-generated description by cubic. -->

## Summary by cubic
Bump version from 0.18.0-beta.1 to the stable 0.18.0. Updates
package.json to finalize the v0.18.0 release for publishing.

<!-- End of auto-generated description by cubic. -->

package.json

@@ -1,7 +1,7 @@
 {
   "name": "dyad",
   "productName": "dyad",
-  "version": "0.18.0-beta.2",
+  "version": "0.18.0",
   "description": "Free, local, open-source AI app builder",
   "main": ".vite/build/main.js",
   "repository": {