Download translations on demand instead of bundling them

Locales are fetched from the Iris repository at runtime into
languages/downloaded and cached against the revision the jar was built
from; the artifact ships only a manifest of the available locales.
IrisLanguage gains a player language service, per-audience snapshots and
an in-game message editor that writes locale overrides. The Bukkit
artifact verifier now fails when any locale file is embedded, and the
modded shadow jars drop the Bukkit-only switcher and editor classes.

build.gradle

@@ -3,8 +3,6 @@ import org.gradle.api.tasks.Copy
 import org.gradle.api.tasks.compile.JavaCompile
 import org.gradle.jvm.tasks.Jar
 import org.gradle.jvm.toolchain.JavaLanguageVersion
-import groovy.json.JsonOutput
-import groovy.json.JsonSlurper
 
 /*
  * Iris is a World Generator for Minecraft Bukkit Servers
@@ -147,16 +145,6 @@ nmsBindings.each { key, value ->
 
 def included = configurations.create('included')
 def jarJar = configurations.create('jarJar')
-def bukkitLanguagesDirectory = layout.buildDirectory.dir('generated/bukkit-languages')
-Set<String> sharedNonEnglishBukkitMessages = [
-    'iris.desktop.vision.fps',
-    'iris.desktop.vision.tiles',
-    'iris.bukkit.runtime.commandpack.message_2',
-    'iris.bukkit.commanddatapack.message_2',
-    'iris.runtime.chunk_job.bossbar.progress',
-    'iris.runtime.studio.action.progress',
-    'iris.runtime.chunk_job.action.progress'
-] as Set
 dependencies {
     nmsBindings.keySet().each { key ->
         add('included', project(path: ":adapters:bukkit:nms:${key}", configuration: 'runtimeElements'))
@@ -166,48 +154,6 @@ dependencies {
     add('jarJar', project(':core:agent'))
 }
 
-def prepareBukkitLanguages = tasks.register('prepareBukkitLanguages') {
-    inputs.files(fileTree(project(':core').file('src/main/resources/languages')) {
-        include('*.json')
-    })
-    outputs.dir(bukkitLanguagesDirectory)
-    doLast {
-        File outputDirectory = bukkitLanguagesDirectory.get().asFile
-        delete(outputDirectory)
-        outputDirectory.mkdirs()
-        List<File> sources = fileTree(project(':core').file('src/main/resources/languages')) {
-            include('*.json')
-        }.files.sort { File left, File right -> left.name <=> right.name }
-        List<Map<String, Object>> catalogs = sources.collect { File source ->
-            (Map<String, Object>) new JsonSlurper().parse(source)
-        }
-        Map<String, Object> referenceMessages = (Map<String, Object>) catalogs.first().get('messages')
-        List<String> messageIds = referenceMessages.keySet()
-                .findAll { String key -> !key.startsWith('iris.modded.') }
-                .sort()
-        Set<String> sharedFallbackIds = new LinkedHashSet<>(messageIds)
-        catalogs.each { Map<String, Object> catalog ->
-            Map<String, Object> messages = (Map<String, Object>) catalog.get('messages')
-            if (!messages.keySet().containsAll(messageIds)) {
-                throw new GradleException("Bundled locale ${catalog.get('locale')} is missing Bukkit messages")
-            }
-            sharedFallbackIds.removeIf { String key -> messages.get(key) != referenceMessages.get(key) }
-        }
-        sharedFallbackIds.removeAll(sharedNonEnglishBukkitMessages)
-
-        sources.eachWithIndex { File source, int index ->
-            Map<String, Object> catalog = catalogs.get(index)
-            Map<String, Object> messages = (Map<String, Object>) catalog.get('messages')
-            List<Object> compactMessages = messageIds.collect { String key ->
-                sharedFallbackIds.contains(key) ? null : messages.get(key)
-            }
-            new File(outputDirectory, source.name).setText(
-                    JsonOutput.toJson([catalog.get('locale'), compactMessages]),
-                    'UTF-8')
-        }
-    }
-}
-
 tasks.named('jar', Jar).configure {
     inputs.files(included)
     duplicatesStrategy = DuplicatesStrategy.EXCLUDE
@@ -216,9 +162,6 @@ tasks.named('jar', Jar).configure {
     from(provider { included.resolve().collect { zipTree(it) } }) {
         exclude('languages/**')
     }
-    from(prepareBukkitLanguages) {
-        into('languages')
-    }
     doFirst {
         delete(layout.buildDirectory.file("libs/Iris-${project.version}.jar"))
     }
@@ -591,6 +534,7 @@ List<String> requiredBukkitArtifactEntries = [
     'paper-plugin.yml',
     'slimjar.dat',
     'slimjar-resolutions.dat',
+    'iris-language-source.properties',
     'agent.jar',
     'art/arcane/iris/Iris.class',
     'art/arcane/iris/IrisBootstrap.class',
@@ -618,7 +562,6 @@ tasks.register('verifyBukkitArtifact') {
         BukkitArtifactVerifier.verify(
                 artifact,
                 requiredBukkitArtifactEntries,
-                17,
                 16,
                 maximumBukkitArtifactBytes)
         logger.lifecycle("Verified ${artifact.name} packaging and class reference graph")