K2 kapt: add kapt.use.k2 Gradle property

... and `-Kapt-use-k2` CLI flag to enable K2 kapt.

 #KT-61114 Fixed

plugins/kapt3/kapt3-cli/src/KaptCli.kt

@@ -107,6 +107,7 @@ private fun transformKaptToolArgs(args: List<String>, messageCollector: MessageC
             }
             KaptCliOption.APT_MODE_OPTION -> aptModePassed = true
             KaptCliOption.VERBOSE_MODE_OPTION -> kaptVerboseModePassed = true
+            KaptCliOption.USE_K2 -> transformed.add("-Xuse-kapt4")
             else -> {}
         }
 

plugins/kapt3/kapt3-cli/src/KaptCliOption.kt

@@ -221,6 +221,13 @@ enum class KaptCliOption(
         cliToolOption = CliToolOption("-Kapt-use-jvm-ir", FLAG)
     ),
 
+    USE_K2(
+        "useK2",
+        "true | false",
+        "Use K2",
+        cliToolOption = CliToolOption("-Kapt-use-k2", FLAG)
+    ),
+
     DETECT_MEMORY_LEAKS_OPTION("detectMemoryLeaks", "true | false", "Detect memory leaks in annotation processors"),
     INCLUDE_COMPILE_CLASSPATH(
         "includeCompileClasspath",