Share test fixtures across modules

- Move art.arcane.iris.testsupport into core/src/testFixtures and apply java-test-fixtures to core
- Consume core test fixtures from the bukkit plugin, nms, probe and the three loader adapters
- Delete the duplicate ProjectPaths copies in the bukkit-plugin and modded-common test trees
- Point ModdedMessageContributorTest at the shared ProjectPaths
- Guard CommandPackCompatTest, NativeTransitionColumnTest and StubPlatformStateTest with PlatformLeakGuard
- Release the probe runtime state after DimensionStackSuperflatProbeTest opens a workspace
- Keep core main classes ahead of the core jar on the test classpath so the bytecode gates still scan a directory

adapters/bukkit/plugin/src/test/java/art/arcane/iris/core/commands/CommandPackCompatTest.java

@@ -7,10 +7,8 @@ import art.arcane.iris.core.pack.PackValidationResult;
 import art.arcane.volmlib.util.director.compat.DirectorAnnotationCompatibility;
 import art.arcane.volmlib.util.director.runtime.DirectorNodeDescriptor;
 import art.arcane.volmlib.util.director.runtime.DirectorParameterDescriptor;
-import art.arcane.iris.spi.IrisPlatform;
-import art.arcane.iris.spi.IrisPlatforms;
-import org.junit.After;
-import org.junit.Before;
+import art.arcane.iris.testsupport.PlatformLeakGuard;
+import org.junit.Rule;
 import org.junit.Test;
 
 import java.util.List;
@@ -20,22 +18,8 @@ import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;
 
 public class CommandPackCompatTest {
-    private IrisPlatform previousPlatform;
-
-    /** The persisted Minecraft version is only used when no platform is bound, so pin that here. */
-    @Before
-    public void unbindPlatform() {
-        previousPlatform = IrisPlatforms.isBound() ? IrisPlatforms.get() : null;
-        IrisPlatforms.unbind();
-    }
-
-    @After
-    public void rebindPlatform() {
-        IrisPlatforms.unbind();
-        if (previousPlatform != null) {
-            IrisPlatforms.bind(previousPlatform);
-        }
-    }
+    @Rule
+    public final PlatformLeakGuard leakGuard = PlatformLeakGuard.clean();
 
     private static CompatFinding block(CompatAction action, String subjectKey) {
         return new CompatFinding(

adapters/bukkit/plugin/src/test/java/art/arcane/iris/testsupport/ProjectPaths.java

@@ -1,82 +0,0 @@
-package art.arcane.iris.testsupport;
-
-import java.io.File;
-import java.net.URISyntaxException;
-import java.net.URL;
-import java.nio.file.Files;
-import java.nio.file.Path;
-import java.security.CodeSource;
-import java.security.ProtectionDomain;
-
-public final class ProjectPaths {
-    private static final Path MODULE_ROOT = resolveModuleRoot();
-    private static final Path REPOSITORY_ROOT = resolveRepositoryRoot(MODULE_ROOT);
-
-    private ProjectPaths() {
-    }
-
-    public static Path moduleRoot() {
-        return MODULE_ROOT;
-    }
-
-    public static Path repositoryRoot() {
-        return REPOSITORY_ROOT;
-    }
-
-    public static Path moduleFile(String relative) {
-        return MODULE_ROOT.resolve(relative).normalize();
-    }
-
-    public static Path repositoryFile(String relative) {
-        return REPOSITORY_ROOT.resolve(relative).normalize();
-    }
-
-    public static File moduleFileAt(String relative) {
-        return moduleFile(relative).toFile();
-    }
-
-    public static File repositoryFileAt(String relative) {
-        return repositoryFile(relative).toFile();
-    }
-
-    private static Path resolveModuleRoot() {
-        ProtectionDomain domain = ProjectPaths.class.getProtectionDomain();
-        CodeSource source = domain == null ? null : domain.getCodeSource();
-        URL location = source == null ? null : source.getLocation();
-
-        if (location != null) {
-            try {
-                Path current = Path.of(location.toURI()).toAbsolutePath().normalize();
-
-                while (current != null) {
-                    Path name = current.getFileName();
-
-                    if (name != null && "build".equals(name.toString()) && current.getParent() != null) {
-                        return current.getParent();
-                    }
-
-                    current = current.getParent();
-                }
-            } catch (URISyntaxException | IllegalArgumentException ignored) {
-                return Path.of("").toAbsolutePath().normalize();
-            }
-        }
-
-        return Path.of("").toAbsolutePath().normalize();
-    }
-
-    private static Path resolveRepositoryRoot(Path moduleRoot) {
-        Path current = moduleRoot;
-
-        while (current != null) {
-            if (Files.isRegularFile(current.resolve("settings.gradle"))
-                    && Files.isDirectory(current.resolve("core/src/main/java"))) {
-                return current;
-            }
-
-            current = current.getParent();
-        }
-
-        return moduleRoot;
-    }
-}