Bump gradle to nixos-unstable (8.12)

app/build.gradle.kts

@@ -49,6 +49,9 @@ kotlin {
     compilerOptions {
         jvmTarget.set(JvmTarget.JVM_1_8)
         optIn.add("kotlin.RequiresOptIn")
+        freeCompilerArgs.addAll(
+            "-Xconsistent-data-class-copy-visibility"
+        )
     }
 }
 

app/src/main/kotlin/org/nixos/gradle2nix/Main.kt

@@ -2,6 +2,7 @@ package org.nixos.gradle2nix
 
 import com.github.ajalt.clikt.core.CliktCommand
 import com.github.ajalt.clikt.core.context
+import com.github.ajalt.clikt.core.main
 import com.github.ajalt.clikt.output.MordantHelpFormatter
 import com.github.ajalt.clikt.parameters.arguments.argument
 import com.github.ajalt.clikt.parameters.arguments.multiple