Migration to hooks

[simolus3]

This issue tracks pending items for the migration to hooks in version 3 of package:sqlite3.

External

• Wait for Dart 3.10 to be stable.

Functionality

• Allow compiling sqlite3 from source
• Platform-specific hook options? If someone asks for this I'll open an issue on hooks instead.
• Native finalizers for statements and databases.

Perhaps we also need an option to download sqlite sources in the hook like in sqlite3_native_assets? But I'm not sure, the default options should be good enough for virtually all use-cases and the rest can vendor sqlite.

Testing

• Restore tests broken with the native assets compilation (probably related to the shared cache being unavailable)
• Expand integration tests to cover custom extension build
• Expand integration tests to cover sqlite3multipleciphers
• Run integration tests on Android
• Migrate examples.

Dependents

• Update and release sqlite3_test.
• Update and release sqlite3_web.

The plan is to rename the v3 branch to main on the first stable release, but keep a v2 branch active for a few more months. That would allow also releasing SQLite updates for users on older Flutter versions for a while. Eventually, sqlite3_flutter_libs needs to be discontinued.