Implemented ViaProxy bootstrap (#4201)

* Implemented ViaProxy bootstrap

* Applied requested changes to code

* Override indra settings to Java 17

* Removed explicit java source/target version

* Added ViaProxy artifact to build.yml

* Added ViaProxy artifact to pullrequest.yml

* Updated ViaProxy API usage

* Implemented floodgate support for ViaProxy

* Depend on stable ViaProxy release

* Initialize command manager and ping passthrough before Geyser#start

* Revert "Initialize command manager and ping passthrough before Geyser#start"

This reverts commit 39356071c4.

* Some ping passthrough improvements

* Merged code properly

* Updated ViaProxy API usage

* Implemented better command handling

* Updated ViaProxy and Geyser API usage

* Combine bootstrap and plugin into one class

* Minor code improvements

* Call Geyser shutdown on plugin disable

* Only call disable if Geyser was enabled once

* Don't send two shutdown done messages

* Use setter for enabled boolean

bootstrap/viaproxy/build.gradle.kts

@@ -0,0 +1,26 @@
+dependencies {
+    api(projects.core)
+}
+
+platformRelocate("net.kyori")
+platformRelocate("org.yaml")
+platformRelocate("it.unimi.dsi.fastutil")
+platformRelocate("org.cloudburstmc.netty")
+
+// These dependencies are already present on the platform
+provided(libs.viaproxy)
+
+application {
+    mainClass.set("org.geysermc.geyser.platform.viaproxy.GeyserViaProxyMain")
+}
+
+tasks.withType<com.github.jengelman.gradle.plugins.shadow.tasks.ShadowJar> {
+    archiveBaseName.set("Geyser-ViaProxy")
+
+    dependencies {
+        exclude(dependency("com.google.*:.*"))
+        exclude(dependency("io.netty:.*"))
+        exclude(dependency("org.slf4j:.*"))
+        exclude(dependency("org.ow2.asm:.*"))
+    }
+}