draft options working; spells won't cast though

Assets/_Project/Scripts/Gameplay/BuilderSpells/BuilderSpellPool.cs

@@ -0,0 +1,68 @@
+// Assets/_Project/Scripts/Gameplay/BuilderSpells/BuilderSpellPool.cs
+using System;
+using UnityEngine;
+using TD.Core;
+
+namespace TD.Gameplay.BuilderSpells
+{
+    /// <summary>
+    /// Scene singleton holding every <see cref="BuilderSpellDefinition"/> available this match,
+    /// authored as a flat array in the inspector for convenience. Internally it builds a
+    /// fixed-size table indexed by <see cref="BuilderSpellKind"/> so lookups are a single array
+    /// access, not a scan.
+    /// </summary>
+    /// <remarks>
+    /// Plain MonoBehaviour: identical on every peer (same assets), so there is nothing to sync.
+    /// The server reads it to resolve casts; clients read it to resolve <see
+    /// cref="BuilderSpellDefinition.ClientPlayVfx"/> and to render the cast hotbar. Mirrors
+    /// <see cref="BuilderEffects.BuilderEffectPool"/> exactly.
+    /// </remarks>
+    public class BuilderSpellPool : MonoBehaviour
+    {
+        public static BuilderSpellPool Instance { get; private set; }
+
+        [Tooltip("Every BuilderSpellDefinition asset available this match. One entry per " +
+                 "BuilderSpellKind — order doesn't matter, Kind on the asset itself decides " +
+                 "its slot.")]
+        [SerializeField] private BuilderSpellDefinition[] spells;
+
+        // Fixed-size, enum-indexed lookup built once in Awake. Sized to the enum's entry count,
+        // not authored count, so an out-of-range Kind is a compile-time impossibility rather
+        // than a bounds check we'd otherwise need on every Get().
+        private BuilderSpellDefinition[] byKind;
+
+        private void Awake()
+        {
+            if (Instance != null && Instance != this)
+            {
+                Debug.LogError("[BuilderSpellPool] Multiple instances detected. Only one per scene.");
+                return;
+            }
+            Instance = this;
+
+            int kindCount = Enum.GetValues(typeof(BuilderSpellKind)).Length;
+            byKind = new BuilderSpellDefinition[kindCount];
+            if (spells == null) return;
+
+            for (int i = 0; i < spells.Length; i++)
+            {
+                var def = spells[i];
+                if (def == null) continue;
+                byKind[(int)def.Kind] = def;
+            }
+        }
+
+        private void OnDestroy()
+        {
+            if (Instance == this) Instance = null;
+        }
+
+        /// <summary>Returns the spell asset for <paramref name="kind"/>, or null if none is
+        /// authored in this pool.</summary>
+        public BuilderSpellDefinition Get(BuilderSpellKind kind)
+        {
+            int i = (int)kind;
+            return (byKind != null && i >= 0 && i < byKind.Length) ? byKind[i] : null;
+        }
+    }
+}