v4.0.0

This new major version is mainly upgrading to Apache Solr version 9.7.0 (SEARCH-685).
That requires full re-indexing. Hopefully, backup archives are available too.
That also upgrades the required Java SE version to 17 (SEARCH-714).

It relies on mbsssss@v-2025-05-13 and mmd-schema@v-2025-04-23.

Helper commands to fetch, load and clean up Solr backup archives have been moved/adapted/improved from musicbrainz-docker and modified to work with Solr 8.9+ backup format and restore API. A helper command is also available to delete all the indexed documents if needed.

Continuous integration tests have been updated, and documentation improved.

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What's Changed

• Mitigation for CVE-2021-44228 by @yvanzo in #47
• Document debugging with Solr Admin Query Screen by @yvanzo in #51
• Minor improvements to HACKING.md for clarity by @reosarevok in #52
• SEARCH-625 (MB Solr): Upgrade Java SE version to 11 by @amCap1712 in #53
• SEARCH-714, SEARCH-685: Upgrade to Java 17 and Solr 9.4.0 by @amCap1712 in #54
• Add GitHub action to test packaging MB Solr with Maven by @alastair in #55
• Update mmd-schema with genre collections by @reosarevok in #57
• Upgrade Solr version to 9.5.0 by @yvanzo in #56
• Upgrade Solr version to 9.6.1 and other dependencies by @yvanzo in #58
• Upgrade Solr version to 9.7.0 and other dependencies by @yvanzo in #59
• SEARCH-732: Downgrade JFlex to 1.6.1 by @mwiencek in #60
• Fix "RAMDirectory can only be used with the 'single' lock factory type." in tests by @mwiencek in #62
• Add helper scripts to handle Solr backup archives by @yvanzo in #61
• Update git submodule mmd-schema to tag v-2025-04-23 by @yvanzo in #64
• Update the documentation by @yvanzo in #65

New Contributors

• @reosarevok made their first contribution in #52

Full Changelog: v3.4.2...v4.0.0