feat: add Nord theme for Yazi

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.gitignore

@@ -19,6 +19,7 @@
 !.config/
 !.config/yazi/
 !.config/yazi/yazi.toml
+!.config/yazi/theme.toml
 !.config/micro/
 !.config/micro/settings.json
 !.config/micro/bindings.json