[BTA tests] Add KDoc to clarify meaning of some symbols

^KT-61860 In Progress

compiler/build-tools/kotlin-build-tools-api-tests/src/testCommon/kotlin/compilation/model/AbstractModule.kt

@@ -60,9 +60,6 @@ abstract class AbstractModule(
     override val icWorkingDir: Path
         get() = buildDirectory.resolve("ic")
 
-    override val snapshotFile: Path
-        get() = icWorkingDir.resolve("$moduleName.snapshot")
-
     override val icCachesDir: Path
         get() = icWorkingDir.resolve("caches")
 

compiler/build-tools/kotlin-build-tools-api-tests/src/testCommon/kotlin/compilation/model/Dependency.kt

@@ -7,10 +7,16 @@ package org.jetbrains.kotlin.buildtools.api.tests.compilation.model
 
 import java.nio.file.Path
 
+/**
+ * Represents a cache key used within the scenario DSL to provide initial build cacheability.
+ * Must properly override the [equals] and [hashCode] methods.
+ */
 interface DependencyScenarioDslCacheKey
 
 interface Dependency {
+    /**
+     * File system location that may be used as a part of JVM classpath.
+     */
     val location: Path
-    val snapshotFile: Path
     val scenarioDslCacheKey: DependencyScenarioDslCacheKey
 }

compiler/build-tools/kotlin-build-tools-api-tests/src/testCommon/kotlin/compilation/model/Module.kt

@@ -15,11 +15,35 @@ import java.nio.file.Path
 interface Module : Dependency {
     val project: Project
     val moduleName: String
+
+    /**
+     * Compiler arguments in the format of the Kotlin compiler CLI
+     */
     val additionalCompilationArguments: List<String>
+
+    /**
+     * Directory containing all the source (.kt) files of the module
+     */
     val sourcesDirectory: Path
+
+    /**
+     * Directory containing all the files and directories that are produced during the compilation process
+     */
     val buildDirectory: Path
+
+    /**
+     * Directory containing compiler output (e.g. `.class` and `.kotlin_module` files)
+     */
     val outputDirectory: Path
+
+    /**
+     * Directory containing all the files and directories related to incremental compilation
+     */
     val icWorkingDir: Path
+
+    /**
+     * Directory containing caches required for incremental compilation
+     */
     val icCachesDir: Path
 
     fun compile(