chore: add spotless, spotbugs, errorprone, and openrewrite

Configure static analysis and code quality tools for consistent
code formatting and automated best-practice enforcement.

Author: AlexProgrammerDE

build.gradle.kts

@@ -2,12 +2,36 @@ plugins {
     base
     java
     id("xyz.jpenilla.run-velocity") version "3.0.2"
+    id("com.diffplug.spotless") version "8.2.1"
+    id("net.ltgt.errorprone") version "4.4.0"
+    id("com.github.spotbugs") version "6.4.8"
+    id("org.openrewrite.rewrite") version "7.25.0"
 }
 
 tasks.named<UpdateDaemonJvm>("updateDaemonJvm") {
     languageVersion = JavaLanguageVersion.of(25)
 }
 
+spotless {
+    java {
+        trimTrailingWhitespace()
+        leadingTabsToSpaces(2)
+        endWithNewline()
+    }
+}
+
+rewrite {
+    activeRecipe("org.openrewrite.staticanalysis.CommonStaticAnalysis")
+    activeRecipe("org.openrewrite.staticanalysis.CodeCleanup")
+    activeRecipe("org.openrewrite.staticanalysis.JavaApiBestPractices")
+    activeRecipe("org.openrewrite.java.migrate.UpgradeToJava25")
+    isExportDatatables = true
+}
+
+spotbugs {
+    ignoreFailures = true
+}
+
 group = "net.blockhost"
 version = "1.0.1"
 
@@ -25,6 +49,13 @@ java {
 }
 
 dependencies {
+    errorprone("com.google.errorprone:error_prone_core:2.46.0")
+    spotbugs("com.github.spotbugs:spotbugs:4.9.8")
+
+    rewrite("org.openrewrite.recipe:rewrite-static-analysis:2.26.0")
+    rewrite("org.openrewrite.recipe:rewrite-migrate-java:3.26.0")
+    rewrite("org.openrewrite.recipe:rewrite-rewrite:0.19.0")
+
     compileOnly("com.velocitypowered:velocity-api:3.4.0")
     annotationProcessor("com.velocitypowered:velocity-api:3.4.0")