Add JUnit 5 test suite with 97 tests covering all classes

- Add test dependencies: JUnit 5, Mockito 5, MockBukkit
- Add jitpack.io repo for MockBukkit snapshots
- Update surefire to 3.5.4 with Java 21 module opens
- Update JaCoCo to 0.8.13 for Java 25 class file support
- Add shared test infrastructure: CommonTestSetup, WhiteBox, TestWorldSettings
- Add tests for all 11 source classes including addon lifecycle,
  commands, manager DB operations, GUI generation, and utilities
- Add CLAUDE.md for Claude Code guidance

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: tastybento

CLAUDE.md

@@ -0,0 +1,62 @@
+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Project Overview
+
+ControlPanel is a BentoBox addon for Minecraft (Paper) that provides customizable GUI menus for players to execute common commands. It supports multiple gamemodes (AcidIsland, BSkyBlock, CaveBlock, SkyGrid, AOneBlock) and 13 localizations.
+
+## Build Commands
+
+```bash
+# Build the project
+mvn clean package
+
+# Run tests
+mvn clean test
+
+# Run tests and SonarCloud analysis (as CI does)
+mvn -B verify
+
+# Run a single test class
+mvn test -Dtest=UtilsTest
+
+# Build without tests
+mvn clean package -DskipTests
+```
+
+**Requires Java 21.** The output JAR is placed in `target/`.
+
+## Testing
+
+Tests use **JUnit 5 + Mockito 5 + MockBukkit**. All integration tests extend `CommonTestSetup` which provides pre-configured mocks for BentoBox, Bukkit, Player, World, Island, and other framework objects.
+
+Key test infrastructure in `src/test/java/world/bentobox/controlpanel/`:
+- `CommonTestSetup.java` — abstract base class with `@BeforeEach`/`@AfterEach` lifecycle, static mocks for `Bukkit` and `Util`
+- `WhiteBox.java` — reflection utility for setting private static fields (e.g., BentoBox singleton)
+- `TestWorldSettings.java` — stub `WorldSettings` implementation for tests
+
+For tests requiring database access, mock `DatabaseSetup` statically and use `WhiteBox.setInternalState(Database.class, "databaseSetup", dbSetup)` to inject the mock handler.
+
+## Architecture
+
+This is a **BentoBox Addon** — it extends BentoBox's `Addon` class and follows its lifecycle (`onLoad` → `onEnable` → `onReload` → `onDisable`).
+
+**Entry point:** `ControlPanelAddon.java` — registers commands, loads settings, initializes the manager.
+
+**Key flow:**
+1. `ControlPanelAddon` hooks `PlayerCommand` and `AdminCommand` into each registered BentoBox gamemode's command tree
+2. `ControlPanelManager` loads/saves `ControlPanelObject` data from YAML files and caches them per-world
+3. `ControlPanelGenerator` builds the GUI using BentoBox's `PanelBuilder` API, resolving button actions, permissions, and placeholders (`[player]`, `[server]`, `[label]`)
+
+**Data model:** `ControlPanelObject` (implements `DataObject`) represents a single control panel with its button layout. The manager parses the YAML template (`controlPanelTemplate.yml`) into these objects.
+
+**Configuration:** `Settings.java` uses BentoBox's `@StoreAt`/`@ConfigEntry` annotations for YAML-backed config. The `config.yml` controls which gamemodes the addon is disabled for.
+
+**Localization:** 13 locale YAML files in `src/main/resources/locales/`. Translation key constants are centralized in `Constants.java`.
+
+**Optional integration:** `ItemsAdderParse.java` provides soft-dependency support for the ItemsAdder plugin's custom items.
+
+## CI
+
+GitHub Actions on push to `develop` and PRs: builds with Maven + runs SonarCloud analysis (project: `BentoBoxWorld_ControlPanel`).

pom.xml

@@ -69,6 +69,9 @@
         <sonar.projectKey>BentoBoxWorld_ControlPanel</sonar.projectKey>
         <sonar.organization>bentobox-world</sonar.organization>
         <sonar.host.url>https://sonarcloud.io</sonar.host.url>
+        <!-- Test dependency versions -->
+        <junit.version>5.10.2</junit.version>
+        <mockito.version>5.11.0</mockito.version>
     </properties>
 
     <profiles>
@@ -104,6 +107,14 @@
 
     <!-- Repositories contains links from were dependencies will be searched -->
     <repositories>
+        <!-- jitpack first so MockBukkit snapshots resolve without hitting other repos -->
+        <repository>
+            <id>jitpack.io</id>
+            <url>https://jitpack.io</url>
+            <snapshots>
+                <enabled>true</enabled>
+            </snapshots>
+        </repository>
         <repository>
             <id>papermc</id>
             <url>https://repo.papermc.io/repository/maven-public/</url>
@@ -128,6 +139,36 @@
 
     <!-- Your addon must contain Paper and BentoBox APIs dependencies. -->
     <dependencies>
+        <dependency>
+            <groupId>com.github.MockBukkit</groupId>
+            <artifactId>MockBukkit</artifactId>
+            <version>v1.21-SNAPSHOT</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.junit.jupiter</groupId>
+            <artifactId>junit-jupiter-api</artifactId>
+            <version>${junit.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.junit.jupiter</groupId>
+            <artifactId>junit-jupiter-engine</artifactId>
+            <version>${junit.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.mockito</groupId>
+            <artifactId>mockito-junit-jupiter</artifactId>
+            <version>${mockito.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.mockito</groupId>
+            <artifactId>mockito-core</artifactId>
+            <version>${mockito.version}</version>
+            <scope>test</scope>
+        </dependency>
         <dependency>
             <groupId>io.papermc.paper</groupId>
             <artifactId>paper-api</artifactId>
@@ -221,11 +262,12 @@
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-surefire-plugin</artifactId>
-                <version>3.1.2</version>
+                <version>3.5.4</version>
                 <!--suppress MavenModelInspection -->
                 <configuration>
                     <argLine>
                         ${argLine}
+                        -XX:+EnableDynamicAgentLoading
                         --add-opens java.base/java.lang=ALL-UNNAMED
                         --add-opens java.base/java.math=ALL-UNNAMED
                         --add-opens java.base/java.io=ALL-UNNAMED
@@ -307,7 +349,7 @@
             <plugin>
                 <groupId>org.jacoco</groupId>
                 <artifactId>jacoco-maven-plugin</artifactId>
-                <version>0.8.10</version>
+                <version>0.8.13</version>
                 <configuration>
                     <append>true</append>
                     <excludes>