Summary:
Before this change, the highest supported block-based table format_version was only available as the internal constant kLatestBbtFormatVersion in table/format.h. Applications that accept a format_version setting from users or configuration (especially for SetOptions()) had no public way to validate it against the linked RocksDB build before applying it.
This adds the public constant
BlockBasedTableOptions::kLatestSupportedFormatVersion (currently 8) and removes kLatestBbtFormatVersion, redirecting all internal and test uses to the new constant. Supported-version checks and option validation are unchanged: format_version above the constant is still rejected as InvalidArgument, and draft format_versions remain usable only under the TEST-only TEST_AllowUnsupportedFormatVersion() hook.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/15397
Test Plan: Same value and same checks, so no new tests. Existing format_version validation coverage (e.g. TableTest.UnsupportedFormatVersionConfigTest) and the FormatLatest test instantiations now go through the public constant.
Reviewed By: rban1
Differential Revision: D125117976
Pulled By: pdillinger
fbshipit-source-id: 67e0c5b7eade4bf649957435aa0b28b187793f7c
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