Release date.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

CHANGELOG

@@ -1,4 +1,4 @@
-?? Sep 2026 - Release 0.31.0
+9 September 2026 - Release 0.31.0
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 * Requires an ES2020-capable JavaScript engine (Node.js 12 or newer).