chore(main): release 2.3.1

[github-actions]

🤖 I have created a release beep boop

2.3.1 (2026-06-18)

Fixes & Enhancements

• Align condition equality with JavaScript strict equality semantics:
  • $eq and direct equality no longer coerce across types, so values like 5 and "5" or true and 1 no longer match. (7f9d2d2)
  • $ne now returns the inverse of strict equality for these cases.
  • Array and object operands follow JavaScript reference-identity semantics, so separately parsed but structurally equal arrays/objects do not match with $eq. (a8ff302, 7f9d2d)
• Fix NaN comparison handling so NaN does not compare equal to itself and ordered comparisons involving NaN evaluate as false. (672136a)
• Preserve JavaScript-compatible Unicode lowercasing behavior for case-insensitive operators such as $ini, $nini, and $alli. (5f45087)

Tests and CI

• Expanded SDK conformance coverage for condition operators, prerequisite/parent-condition cases, force-rule hashVersion: 2, and sticky-bucket bucket-version boundaries.
  (505c8e1, a95ce02, 076eab8)
• Added a corpus freshness check against the JavaScript SDK cases corpus to catch missing or drifted cases.
  (e428acb, 460f581, a030b66)

---

This PR was generated with Release Please. See documentation.

[github-actions]

🤖 Release is at https://github.com/growthbook/growthbook-python/releases/tag/v2.3.1 🌻