Release checklist

[simolus3]

This is a checklist to track the release of v0.4.0.

Changes (quite a big one):

• Add helper function to fix JS subkey encoding #75
• Fix typo in JS key encoding fix function #76
• Rewrite the "sync_local" query #78
• sync_local: Re-use prepared statements #79
• Add checksum newtype #80
• Use serde to read tables and indexes from schema #81
• Use serde to parse data lines and checkpoints #82
• Update Rust toolchain #83
• Avoid allocation in deserialize to i64 #84

Core build (this repo):

• Release PR: Prepare 0.4.0 release #86.
• GitHub Release
• Android aar released on Maven Central
• Cocoapod released

SQLite + powersync bundles:

• react-native-quick-sqlite: Update powersync-sqlite-core to 0.4.0 react-native-quick-sqlite#87
• wa-sqlite build: Update powersync-sqlite-core to 0.4.0 wa-sqlite#38

User-facing SDK updates:

• powersync.dart: Update powersync-sqlite-core to 0.4.0 powersync.dart#291
• powersync-js: (blocked on the releasing the bundles)
• kotlin: Update powersync-sqlite-core to 0.4.0 powersync-kotlin#200
• swift: Support version 0.4.0 of powersync-sqlite-core powersync-swift#49