Implement Pkl binary renderer and parser (#1203)

Implements a binary renderer for Pkl values, which is a lossless capturing of Pkl data.

This follows the pkl binary format that is already used with `pkl server` calls, and is
made available as a Java API and also an in-language API.

Also, introduces a binary parser into the corresponding `PObject` types in Java.

pkl-config-kotlin/pkl-config-kotlin.gradle.kts

@@ -30,6 +30,7 @@ val buildInfo = project.extensions.getByType<BuildInfo>()
 dependencies {
   pklCodegenKotlin(projects.pklCodegenKotlin)
   implementation(libs.kotlinReflect)
+  implementation(libs.msgpack)
 
   // Don't declare a runtime dependency to pkl-config-java because Gradle cannot resolve
   // the correct publication (library vs fatJar) when generating the POM.