[Build] Migrate most of the build logic from Project.buildDir usage

It's going to be deprecated in Gradle 8.3

There's currently no way to pass a `org.gradle.api.provider.Provider` to the JavaExec.systemProperty or Test.systemProperty. There's a workaround using `org.gradle.process.CommandLineArgumentProvider`, but I intentionally don't rework these calls as Gradle is going to allow passing providers to configure system properties: https://github.com/gradle/gradle/issues/12247#issuecomment-1568427242
^KTI-1473 In Progress

prepare/compiler/build.gradle.kts

@@ -80,8 +80,6 @@ val buildNumber by configurations.creating
 
 val compilerBaseName = name
 
-val outputJar = fileFrom(buildDir, "libs", "$compilerBaseName.jar")
-
 val compilerModules: Array<String> by rootProject.extra
 
 val distLibraryProjects = listOfNotNull(
@@ -261,7 +259,7 @@ val distSbomTask = configureSbom(
 
 val packCompiler by task<Jar> {
     duplicatesStrategy = DuplicatesStrategy.EXCLUDE
-    destinationDirectory.set(File(buildDir, "libs"))
+    destinationDirectory.set(layout.buildDirectory.dir("libs"))
     archiveClassifier.set("before-proguard")
 
     dependsOn(fatJarContents)
@@ -315,7 +313,7 @@ val proguard by task<CacheableProguardTask> {
         provider { packCompiler.get().outputs.files.singleFile }
     )
 
-    outjars(fileFrom(buildDir, "libs", "$compilerBaseName-after-proguard.jar"))
+    outjars(layout.buildDirectory.file("libs/$compilerBaseName-after-proguard.jar"))
 
     libraryjars(mapOf("filter" to "!META-INF/versions/**"), proguardLibraries)
     libraryjars(
@@ -340,7 +338,7 @@ val proguard by task<CacheableProguardTask> {
         )
     )
 
-    printconfiguration("$buildDir/compiler.pro.dump")
+    printconfiguration(layout.buildDirectory.file("compiler.pro.dump"))
 }
 
 val pack = if (kotlinBuildProperties.proguard) proguard else packCompiler