Release checklist v0.3.12

[simolus3]

This is a checklist to track the release of v0.3.12.

Changes:

• (0.3.12) Fix duplicate entries in ps_sync_state #63

Core build (this repo):

• Release PR: Fix duplicate entries in ps_sync_state #63.
• GitHub Release: https://github.com/powersync-ja/powersync-sqlite-core/releases/tag/v0.3.12
• Android aar released on Maven Central
• Cocoapod released

SQLite + powersync bundles:

• react-native-quick-sqlite: Update core extension to 0.3.12 react-native-quick-sqlite#77
• wa-sqlite build: Update powersync version wa-sqlite#32

User-facing SDK updates:

• powersync.dart: Update core extension to 0.3.12 powersync.dart#250
• powersync-js: (blocked on the releasing the bundles)
• kotlin & swift: Update core extension to 0.3.12 powersync-kotlin#140