Fix: Update LenientNanInfinityTest to use unsafe mode for package-private classes

- Added .useUnsafe(true) to ReadOptions for deserializing package-private outer class
- Required due to ThreadLocal unsafe mode changes in java-util 4.0.1
- Updated changelog with unsafe mode feature documentation

🤖 Generated with Claude Code (https://claude.ai/code)

Co-Authored-By: Claude <[email protected]>

Author: jdereg

changelog.md

@@ -1,5 +1,6 @@
 ### Revision History
 #### 4.61.0 (Unreleased)
+* **FEATURE**: Added `useUnsafe` option to `ReadOptions` to control unsafe object instantiation. When enabled, json-io can deserialize package-private classes, inner classes, and classes without accessible constructors. This feature is opt-in for security reasons and uses thread-local settings to prevent interference between concurrent deserializations.
 * **TEST**: Fixed `DistanceBetweenClassesTest.testPrimitives` to accommodate changes in java-util 4.0.1's `ClassUtilities.computeInheritanceDistance()` method. The method now correctly recognizes primitive widening conversions (e.g., byte to int returns distance 2, short to int returns distance 1).
 * **FIX**: PR #426 - Windows compatibility fixes for json-io:
   * Fixed `JsonObject.CacheState` to implement `Serializable` for proper Java serialization support

src/test/java/com/cedarsoftware/io/LenientNanInfinityTest.java

@@ -79,7 +79,10 @@ private void testFloatDouble(float float1, double double1)
         TestUtil.printLine("a = " + a);
         TestUtil.printLine("json = " + json);
 
-        ReadOptions readOptions = new ReadOptionsBuilder().allowNanAndInfinity(true).build();
+        ReadOptions readOptions = new ReadOptionsBuilder()
+                .allowNanAndInfinity(true)
+                .useUnsafe(true)  // Enable unsafe mode for package-private outer class
+                .build();
         A newA = (A) TestUtil.toObjects(json, readOptions, null);
         TestUtil.printLine("newA = " + newA);