Prepare OpenASO 0.4.3

[hubab1]

Release

• bump OpenASO from 0.4.2 (build 8) to 0.4.3 (build 9)
• release the merged official Apple Ads Search Term Popularity integration and V6 production-database migration

Pre-release validation

• PR Add official Apple Ads search popularity #81 passed GitHub CI and was squash-merged into main
• 684 local tests passed across 60 suites
• clean Debug and unsigned universal arm64/x86_64 Release builds passed
• a 2.3 GB production database copy migrated to V6 with exact legacy/normalized equality, zero legacy rows remaining, and SQLite quick_check = ok
• a refresh triggered through the final app UI updated the production-copy flight tracker popularity from stale 61 to fresh 60 and persisted appleAdsPopularity without an error

After this PR merges, the manual release workflow will generate the changelog/release notes, sign and notarize the app and DMG, publish the Sparkle appcast and R2 artifacts, tag v0.4.3, and create the GitHub release.