Update changelogs from fern repo (#1664)

Co-authored-by: tstanmay13 <[email protected]>

Author: fern-support

fern/products/sdks/overview/java/changelog/2025-10-31.mdx

@@ -0,0 +1,21 @@
+## 3.11.0
+**`(feat):`** Add support for three-state nullable fields in PATCH requests via `collapse-optional-nullable` config.
+When enabled, optional nullable fields use `OptionalNullable<T>` to distinguish between omitted fields,
+explicit null values, and actual values. This enables proper PATCH request semantics for APIs that need
+to differentiate between "not specified" and "set to null".
+
+```yaml
+customConfig:
+  collapse-optional-nullable: true
+```
+
+Generated usage:
+```java
+UpdateRequest.builder()
+    .fieldName(OptionalNullable.absent())    // Omit field
+    .anotherField(OptionalNullable.ofNull()) // Clear field
+    .valueField(OptionalNullable.of("value")) // Set value
+    .build();
+```
+
+