v0.9.55

Changelog

• 3e85140 docs: Define a lossless build history transition
• 1a8e067 builds: Preserve history when upgrading to module builds

Release notes

• Servers with existing build records can complete the migration to module-based builds
  without losing historical records.
• Earlier builds and events are preserved in the build_history database schema, outside
  the current build UI; new build IDs cannot reuse historical IDs.
• Rolling back the module transition refuses to discard new builds and is available
  only while the new build model is empty.

🤖 Drafted by Codex on chakrit's behalf.