Slot implementation and refactor of loader

build.gradle

@@ -1 +1,7 @@
 apply from: 'https://raw.githubusercontent.com/ldtteam/OperaPublicaCreator/ng7/gradle/mod.gradle'
+
+runs {
+    client {
+        systemProperty 'blockui.debug', 'true'
+    }
+}

gradle.properties

@@ -6,7 +6,7 @@ org.gradle.configuration-cache=true
 
 modId=blockui
 modGroup=com.ldtteam
-modVersion=0.0.1
+modVersion=1.0.200
 
 javaVersion=21
 useJavaToolChains=true

settings.gradle

@@ -1,4 +1,4 @@
 gradle.startParameter.setProjectProperties(new HashMap<>(gradle.startParameter.getProjectProperties()))
 gradle.startParameter.getProjectProperties().put("build.start", Long.toString(System.currentTimeMillis()))
 
-rootProject.name = "blockui"
+rootProject.name = "blockui"

src/main/java/com/ldtteam/blockui/LayoutContext.java

@@ -0,0 +1,30 @@
+package com.ldtteam.blockui;
+
+import org.jetbrains.annotations.Nullable;
+
+import java.util.Map;
+
+/**
+ * Carries slot content and an optional position override during layout expansion.
+ * Each slot name maps to exactly ONE PaneParams (slots are unique).
+ * {@code null} slot name in the caller is normalized to {@link #DEFAULT_SLOT_KEY}.
+ * {@code posOverride} is non-null when the use-site {@code <layout>} tag specifies a {@code pos}, {@code x}, or {@code y} attribute,
+ * in which case the layout file's single root child has its position replaced with these values.
+ */
+public record LayoutContext(Map<String, PaneParams> slotContent, @Nullable int[] posOverride)
+{
+    public static final LayoutContext EMPTY = new LayoutContext(Map.of(), null);
+
+    static final String DEFAULT_SLOT_KEY = "default";
+
+    @Nullable
+    public PaneParams get(final String slotName)
+    {
+        return slotContent.get(slotName);
+    }
+
+    public boolean hasPosOverride()
+    {
+        return posOverride != null;
+    }
+}