Added encounter registry

Runtime/EncounterRegistry.cs

@@ -56,6 +56,73 @@ namespace Jovian.EncounterSystem {
                 }
             }
         }
+        public EncounterTable GetEncounterTable(string id) {
+            foreach(var collection in encounterCollections) {
+                foreach(var table in collection.encounterTables) {
+                    if(table.id == id) {
+                        return table;
+                    }
+                }
+            }
+            return null;
+        }
+
+         public IEncounter GetRandomEncounter(string encounterTableId) {
+             var table = GetEncounterTable(encounterTableId);
+             if(!table) {
+                 return null;
+             }
+             var ec = table.encounters;
+            return ec[UnityEngine.Random.Range(0, ec.Count)];
+        }
+
+        /// <summary>Random pick restricted to encounters whose runtime type matches <paramref name="type"/>.
+        /// Zero-alloc — uses reservoir sampling instead of building an intermediate filtered list.</summary>
+        public IEncounter GetRandomEncounter(string encounterTableId, IEncounterKind encounterKind) {
+            var table = GetEncounterTable(encounterTableId);
+            if(!table || encounterKind == null) {
+                return null;
+            }
+
+            IEncounter selected = null;
+            var seen = 0;
+            for(var i = 0; i < encounters.Count; i++) {
+                var encounter = table.encounters[i];
+                if(encounter == null || encounter.GetType() != encounterKind.GetType()) {
+                    continue;
+                }
+                seen++;
+                if(UnityEngine.Random.Range(0, seen) == 0) {
+                    selected = encounter;
+                }
+            }
+            return selected;
+        }
+
+        /// <summary>Random pick restricted by <paramref name="filter"/>. Used with
+        /// <see cref="QuestProgress.IsGated"/> to exclude gated encounters. Zero-alloc via reservoir sampling.</summary>
+        public IEncounter GetRandomEncounter(Predicate<IEncounter> filter, string encounterTableId) {
+            var table = GetEncounterTable(encounterTableId);
+            if(!table) {
+                return null;
+            }
+            if(filter == null) {
+                return GetRandomEncounter(encounterTableId);
+            }
+
+            IEncounter selected = null;
+            var seen = 0;
+            foreach(var encounter in table.encounters) {
+                if(encounter == null || !filter(encounter)) {
+                    continue;
+                }
+                seen++;
+                if(UnityEngine.Random.Range(0, seen) == 0) {
+                    selected = encounter;
+                }
+            }
+            return selected;
+        }
     }
 
 #if UNITY_EDITOR