ROADMAP: point Planned at the open feature issues

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LpkeXQPaUhxjgqdqnk6BrJ

Author: TMHSDigital

ROADMAP.md

@@ -21,6 +21,7 @@ missing entry, so freshness and accuracy come before volume.
 
 ## Planned
 
+The [open issues labelled `feature` or `enhancement`](https://github.com/TMHSDigital/Free-Game-Dev-Assets/issues?q=is%3Aopen+label%3Afeature%2Cenhancement) are the current plan.
 
 ## Done