Migrate FightSystem modes and countdowns to GameCore

- Move shared arena-mode abstractions into GameCore
- Adapt fight countdowns and APIs to the shared model
- Add SteamWar issue audit workflow and SQL language settings

MissileWars/build.gradle.kts

@@ -24,6 +24,7 @@ plugins {
 dependencies {
     compileOnly(libs.classindex)
     annotationProcessor(libs.classindex)
+    compileOnly(project(":GameCore", "default"))
     compileOnly(project(":SpigotCore", "default"))
 
     compileOnly(libs.paperapi)
@@ -36,6 +37,8 @@ tasks.register<FightServer>("MissileWars21") {
     group = "run"
     description = "Run a 1.21 Dev MissileWars"
     dependsOn(":SpigotCore:shadowJar")
+    dependsOn(":KotlinCore:shadowJar")
+    dependsOn(":GameCore:jar")
     dependsOn(":MissileWars:jar")
     template = "MissileWars"
     worldName = "Great_Wall"