Prepare 0.4.2 release (#48)

Author: bioball

VERSION.txt

@@ -1 +1 @@
-0.4.1
+0.4.2

docs/antora.yml

@@ -1,5 +1,5 @@
 name: swift
 title: Pkl Swift Bindings
-version: 0.4.1
+version: 0.4.2
 nav:
   - nav.adoc

docs/modules/ROOT/pages/CHANGELOG.adoc

@@ -1,5 +1,18 @@
 = Changelog
 
+[[release-0.4.2]]
+== 0.4.2 (2025-04-14)
+
+=== Fixes
+
+* Fixes an issue where enum keys fail to be decoded (https://github.com/apple/pkl-swift/pull/45[#45]).
+* Fixes an issue where unions of ints can possibly be decoded incorrectly (https://github.com/apple/pkl-swift/pull/47[#47]).
+
+=== Miscellaneous
+
+* Auto-generate DocC documentation in the Swift Package Index (https://github.com/apple/pkl-swift/pull/41[#41]).
+* Update license headers (https://github.com/apple/pkl-swift/pull/43[#43]).
+
 [[release-0.4.1]]
 == 0.4.1 (2025-02-04)