Make the compiler accept Json configuration files (#5516)

* Use json files as intermediate results

* fix Gradle tests

* Trying to pass kotlin options to the java codegen (or vice versa) is now a warning

* naming + tweak visibility

* restore proper warning for missing packageName

* remove data classes

* tweak Java API

* cosmetics

* move packageName check to generateOptions task

gradle/libraries.toml

@@ -144,7 +144,6 @@ kotlin-node = "org.jetbrains.kotlin-wrappers:kotlin-node:18.16.12-pre.634"
 kotlinx-serialization-plugin = { group = "org.jetbrains.kotlin", name = "kotlin-serialization", version.ref = "kotlin-plugin" }
 kotlinx-serialization-core = { group = "org.jetbrains.kotlinx", name = "kotlinx-serialization-core", version.ref = "kotlinx-serialization-runtime" }
 kotlinx-serialization-json = { group = "org.jetbrains.kotlinx", name = "kotlinx-serialization-json", version.ref = "kotlinx-serialization-runtime" }
-kotlinx-serialization-json-okio = { group = "org.jetbrains.kotlinx", name = "kotlinx-serialization-json-okio", version.ref = "kotlinx-serialization-runtime" }
 kotlinx-binarycompatibilityvalidator = { group = "org.jetbrains.kotlinx", name = "binary-compatibility-validator", version = "0.13.2" }
 ksp = { module = "com.google.devtools.ksp:symbol-processing-gradle-plugin", version.ref = "ksp" }
 ksp-api = { module = "com.google.devtools.ksp:symbol-processing-api", version.ref = "ksp" }

libraries/apollo-compiler/build.gradle.kts

@@ -18,7 +18,6 @@ dependencies {
   api(libs.poet.java)
 
   implementation(libs.kotlinx.serialization.json)
-  implementation(libs.kotlinx.serialization.json.okio)
 
   testImplementation(libs.kotlin.compiletesting)
   testImplementation(libs.google.testing.compile)