[KPM] Implement initial IdeaKotlinProjectModelBuilder

- Introduce `kotlin-gradle-plugin-idea` module that allows
to share models between the IDE and KGP

- Add `kotlin-gradle-plugin-idea` to the RuntimePublicAPITest to
ensure binary compatibility

^KT-51262

libraries/tools/binary-compatibility-validator/build.gradle

@@ -14,6 +14,7 @@ dependencies {
     testArtifacts project(':kotlin-stdlib-jdk7')
     testArtifacts project(':kotlin-stdlib-jdk8')
     testArtifacts project(':kotlin-reflect')
+    testArtifacts project(':kotlin-gradle-plugin-idea')
 }
 
 pill {