Merge pull request #22 from jwyce/changeset-release/main

Author: jwyce

.changeset/tasty-mangos-sneeze.md

@@ -1,5 +1,32 @@
 # gungi.js
 
+## 3.2.1
+
+### Patch Changes
+
+- f8f09bd: 🔧 prevent duplicate piece IDs in state transitions
+
+  Addresses race conditions in rapid `load()` calls where same piece
+  type/color could receive identical IDs, breaking game state integrity.
+
+  - `applyCanonicalToMissingIds` used flawed conflict detection
+  - Arata moves assigned same ID to both board and hand pieces
+  - Race conditions during rapid state transitions
+
+  Fixed core ID assignment logic with `Set`-based conflict tracking
+  rather than real-time array scanning. Balanced two requirements:
+
+  **Stability**: Preserve IDs across close FEN states (critical for UX)
+  **Uniqueness**: Ensure no duplicate IDs ever persist in system
+
+  - `ensureUniqueIdsLenient()`: Minimal fixes, preserves stability
+  - `ensureUniqueIds()`: Complete reassignment for canonical states
+  - `checkForDuplicateIds()`: Detection without modification
+
+  Arata moves now maintain hand piece ID stability while giving
+  board pieces new IDs, eliminating the duplicate scenario without
+  breaking expected behavior.
+
 ## 3.2.0
 
 ### Minor Changes

CHANGELOG.md

@@ -1,6 +1,6 @@
 {
 	"name": "gungi.js",
-	"version": "3.2.0",
+	"version": "3.2.1",
 	"type": "module",
 	"description": "library which contains all the necessary logic for the strategy game from the HUNTER×HUNTER manga",
 	"main": "lib/gungi.js",