Add changelog entry

Author: nojaf

CHANGELOG.md

@@ -35,6 +35,7 @@
 - Stdlib namespace for Core modules (fixes name clashes with user modules). https://github.com/rescript-lang/rescript/pull/7285
 - Fix runtime type check for Object in untagged variants when one variant case is `null`. https://github.com/rescript-lang/rescript/pull/7303
 - Fix files that were being truncated when sent to the CDN over FTP. https://github.com/rescript-lang/rescript/pull/7306
+- Fix better editor completion for applications. https://github.com/rescript-lang/rescript/pull/7291
 
 #### :house: Internal