Refactor and add generators for keystatic and package

The changes include refactoring the create-reader in cms keystatic and changing @keystatic/next version. Additionally, code generators for keystatic and package have been added, and corresponding templates have been organized into their respective directories.

packages/cms/keystatic/src/index.ts

@@ -1,2 +1,3 @@
 export * from './keystatic-client';
 export * from './content-renderer';
+export * from './keystatic.config';