Protect preference keys from obfuscation

Author: Mahmud0808

app/proguard-rules.pro

@@ -96,4 +96,9 @@
 
 # Keep all drawable resources
 -keep class androidx.compose.ui.res.** { *; }
--keepclassmembers class **.R$drawable { <fields>; }
+-keepclassmembers class **.R$drawable { <fields>; }
+
+# Preference keys
+-keepclassmembers enum com.drdisagree.iconify.data.keys.** {
+    <fields>;
+}