Use rune natural attack speed for unarmed mobs

Unarmed mobs used a flat 5000 ms swing delay. Parse rune_naturalattacks
from the rune template and use its speed (x100 ms) instead, with the
AttackDelay modifier and 1.0 s floor applied as for weapons. Siege
engines now fire every 17.5 s (speed 175); most creatures swing every 3.5 s.
Falls back to 5000 ms when the rune has no natural attack.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/engine/objects/ItemTemplate.java

@@ -138,6 +138,10 @@ public class ItemTemplate {
     public final EnumSet<mbEnums.MobBehaviourType> rune_group_role_set = EnumSet.noneOf(mbEnums.MobBehaviourType.class);
     public boolean rune_renderable = false;
     public int rune_natural_power_attack;
+    // [AI] One float[] per rune_naturalattacks entry. Layout inferred from game data, not yet verified in IDA:
+    // [0] attack speed (x100 ms), [1] range, [2] ?, [3] hand (1 = right, 2 = left), [4] weapon/ammo template id,
+    // [5] projectile speed?, [6] swing anim, [7] damage type index, [8] min damage, [9] max damage
+    public final ArrayList<float[]> rune_natural_attacks = new ArrayList<>();
     public final HashMap<String, String> rune_sparse_data = new HashMap<>();
     public final HashMap<String, int[]> rune_skill_adj = new HashMap<>();
     public final EnumSet<mbEnums.MonsterType> rune_enemy_monster_types = EnumSet.noneOf(mbEnums.MonsterType.class);
@@ -554,6 +558,21 @@ public class ItemTemplate {
                 rune_renderable = jsonObject.getBoolean("rune_renderable");
                 rune_natural_power_attack = jsonObject.getInt("rune_natural_power_attack");
 
+                if (jsonObject.has("rune_naturalattacks")) {
+
+                    JSONArray natural_attacks_json = jsonObject.getJSONArray("rune_naturalattacks");
+
+                    for (Object attackEntry : natural_attacks_json) {
+                        JSONArray attackArray = (JSONArray) attackEntry;
+                        float[] attack = new float[attackArray.length()];
+
+                        for (int i = 0; i < attackArray.length(); i++)
+                            attack[i] = attackArray.getFloat(i);
+
+                        rune_natural_attacks.add(attack);
+                    }
+                }
+
                 JSONObject rune_sparse_json = jsonObject.getJSONObject("rune_sparse_data");
 
                 for (String sparseType : rune_sparse_json.keySet()) {