refactor: reorganize packages and replace LPSchematic with WorldEdit

Restructure core modules into subpackages (generator, schematic, config, session, etc.); add .schem/.nbt schematic pipeline, commands, adaptive stats skeleton, and bootstrap wiring.

src/main/java/dev/loki/loparkour/util/gui/PagedMenu.java

@@ -0,0 +1,42 @@
+package dev.loki.loparkour.util.gui;
+
+import dev.loki.loparkour.config.locale.Locales;
+import dev.loki.loparkour.util.item.Item;
+import org.bukkit.entity.Player;
+
+import java.util.List;
+
+/**
+ * Legacy paged menu stub — real menus use LoLib GUI.
+ */
+public class PagedMenu {
+    private final int rows;
+    private final String title;
+    private List<Item> items = List.of();
+
+    public PagedMenu(int rows, String title) {
+        this.rows = rows;
+        this.title = title;
+    }
+
+    public PagedMenu addToDisplay(List<Item> items) {
+        this.items = items;
+        return this;
+    }
+
+    public PagedMenu item(int slot, Item item) {
+        return this;
+    }
+
+    public PagedMenu nextPage(int slot, Item item) {
+        return this;
+    }
+
+    public PagedMenu prevPage(int slot, Item item) {
+        return this;
+    }
+
+    public void open(Player player) {
+        Locales.send(player, "other.paged_menu_unavailable", title, rows, items.size());
+    }
+}