[kotlinp] Split :tools:kotlinp into "common" and "jvm" subprojects

The "common" subproject keeps only backend-neutral logic and depends
only on :kotlinx-metadata library. It takes the name of the former
project - :tools:kotlinp

The "jvm" subproject depends on the "common" one and also depends
on :kotlinx-metadata-jvm. It gets the new name - :tools:kotlinp-jvm

There is a lot of touched files in this commit. The majority of them
is just moved files (tests, test data, etc).

Only the following files were actually modified:
  .space/CODEOWNERS
  build.gradle.kts
  libraries/tools/abi-comparator/build.gradle.kts
  libraries/tools/kotlinp/build.gradle.kts
  libraries/tools/kotlinp/jvm/build.gradle.kts
  plugins/kapt3/kapt3-compiler/build.gradle.kts
  settings.gradle

 ^KT-62340

libraries/tools/kotlinp/jvm/testData/MultiFileClass.txt

@@ -0,0 +1,23 @@
+// test/File.class
+// ------------------------------------------
+multi-file class {
+  // test/File__MultiFileClassKt
+}
+// test/File__MultiFileClassKt.class
+// ------------------------------------------
+package {
+  // facade: test/File
+
+  // field: x:I
+  public final const val x: kotlin/Int /* = ... */
+    public final get
+
+  // module name: test-module
+}
+// META-INF/test-module.kotlin_module
+// ------------------------------------------
+module {
+  package test {
+    test/File__MultiFileClassKt (test/File)
+  }
+}