Credit Claude Code: note at the top of the README, in CREDITS and the standalone file; pixel-art mark with link next to the licence on title and login screens

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

README.md

@@ -1,5 +1,8 @@
 # DungeonCraft
 
+> **Made with the help of [Claude Code](https://claude.com/claude-code).** The code, graphics, texts and
+> documentation of this game were written together with Claude Code, Anthropic's AI coding assistant.
+
 An original dungeon building & defence game that runs in the browser (Rust + [macroquad](https://github.com/not-fl3/macroquad), compiled to WebAssembly).
 
 Dig out your underground realm, claim the portal to attract creatures, keep them fed, rested and paid, fend off endless hero waves that adapt to your army – and finally destroy the Hero Gate.