[kotlinp] Support rendering KLIB metadata using "kotlinp" format

This commit includes:
1. New subproject :tools:kotlinp-klib that contains the facade for
   rendering the metadata in "kotlinp" format given just
   KlibModuleMetadata
2. A tool for computing (external) IR signatures that are not directly
   available in metadata: KlibKotlinpExternalSignatureComputer

^KT-62340

settings.gradle

@@ -207,6 +207,7 @@ include ":kotlin-imports-dumper-compiler-plugin",
         ":generators:tree-generator-common",
         ":tools:kotlinp",
         ":tools:kotlinp-jvm",
+        ":tools:kotlinp-klib",
         ":kotlin-build-tools-enum-compat",
         ":kotlin-gradle-compiler-types",
         ":kotlin-gradle-plugin-api",
@@ -768,6 +769,7 @@ project(':kotlin-assignment-compiler-plugin.embeddable').projectDir = "$rootDir/
 
 project(':tools:kotlinp').projectDir = "$rootDir/libraries/tools/kotlinp" as File
 project(':tools:kotlinp-jvm').projectDir = "$rootDir/libraries/tools/kotlinp/jvm" as File
+project(':tools:kotlinp-klib').projectDir = "$rootDir/libraries/tools/kotlinp/klib" as File
 project(":kotlin-build-tools-enum-compat").projectDir = "$rootDir/libraries/tools/kotlin-build-tools-enum-compat" as File
 project(':kotlin-gradle-compiler-types').projectDir = "$rootDir/libraries/tools/kotlin-gradle-compiler-types" as File
 project(':kotlin-gradle-plugin-api').projectDir = "$rootDir/libraries/tools/kotlin-gradle-plugin-api" as File