feat: implement HardcoreMode with reward reset on fall

src/main/java/dev/loki/loparkour/mode/HardcoreMode.java

@@ -0,0 +1,83 @@
+package dev.loki.loparkour.mode;
+
+import dev.loki.loparkour.config.Config;
+import dev.loki.loparkour.config.Locales;
+import dev.loki.loparkour.generator.ParkourGenerator;
+import dev.loki.loparkour.leaderboard.Leaderboard;
+import dev.loki.loparkour.player.ParkourPlayer;
+import dev.loki.loparkour.session.Session;
+import dev.loki.loparkour.util.Item;
+import org.bukkit.entity.Player;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+/**
+ * Hardcore Mode — lose all collected rewards on fall.
+ */
+public class HardcoreMode implements Mode {
+
+    private final Leaderboard leaderboard = new Leaderboard(getName(), Leaderboard.Sort.SCORE);
+
+    @Override
+    @NotNull
+    public String getName() {
+        return "hardcore";
+    }
+
+    @Override
+    @Nullable
+    public Item getItem(String locale) {
+        return Locales.getItem(locale, "play.single.hardcore");
+    }
+
+    @Override
+    @NotNull
+    public Leaderboard getLeaderboard() {
+        return leaderboard;
+    }
+
+    @Override
+    public void create(Player player) {
+        if (!Config.CONFIG.getBoolean("joining")) {
+            player.sendMessage("Joining is currently disabled.");
+            return;
+        }
+
+        ParkourPlayer pp = ParkourPlayer.getPlayer(player);
+        if (pp != null && pp.session.generator instanceof HardcoreGenerator) {
+            return;
+        }
+
+        player.closeInventory();
+        Session.create(session -> new HardcoreGenerator(session), null, null, player);
+    }
+
+    // ── HardcoreGenerator ─────────────────────────────────────────────────────
+
+    private static class HardcoreGenerator extends ParkourGenerator {
+
+        private final boolean resetRewards;
+
+        public HardcoreGenerator(@NotNull Session session) {
+            super(session);
+            this.resetRewards = Config.CONFIG.isPath("modes.hardcore.reset-rewards")
+                ? Config.CONFIG.getBoolean("modes.hardcore.reset-rewards") : true;
+        }
+
+        @Override
+        public void fall() {
+            if (resetRewards) {
+                for (ParkourPlayer pp : getPlayers()) {
+                    pp.collectedRewards.clear();
+                }
+            }
+
+            super.fall();
+        }
+
+        @Override
+        public Mode getMode() {
+            return Modes.HARDCORE;
+        }
+    }
+}