[form] Fix exports definitions

Author: x0k

.changeset/calm-grapes-smell.md

@@ -0,0 +1,5 @@
+---
+"@sjsf/form": patch
+---
+
+Fix exports definitions

packages/form/package.json

@@ -80,7 +80,7 @@
     },
     "./focus-on-first-error": {
       "types": "./dist/focus-on-first-error.d.ts",
-      "default": "./dist/focus-on-first-error.js"
+      "svelte": "./dist/focus-on-first-error.js"
     }
   }
 }