v2.18.4

What's Changed

• Ensure that stale values are erased from vertex map by @cqc-alec in #2238
• Fix endianness of nested Conditional values in GreedyPauliSimp by @cqc-alec in #2239
• Update to nanobind 3.1.0. by @cqc-alec in #2240
• Update changelog for 2.18.4 release by @cqc-alec in #2241

Full Changelog: v2.18.3...v2.18.4