GH-3431: Ignore incomplete compaction directories when finding TDB2 storage

[Duansg]

GitHub issue resolved #3431

Pull request Description:

If a TDB2 compaction is interrupted (e.g. the process is killed), a Data-NNNN-tmp directory is left in the database directory. It is cleaned up when the database is connected, but DatabaseOps.findStorageLocation is called earlier by Fuseki (DSGSetup → TDBOps.isTDB2 → SpotTDB2) and throws DBOpEnvException: Invalid filename for matching: Data-0002-tmp, so Fuseki fails to start.

This change makes scanForDirByPattern skip compaction temporary directories (Data-NNNN-tmp). Other unexpected Data* names still raise an error.

Added TestDatabaseCompact.compact_recovery_2, which fails without the fix. All jena-tdb2 tests pass.

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• Tests are included.
• Documentation change and updates are provided for the Apache Jena website
• Commits have been squashed to remove intermediate development commit messages.
• Key commit messages start with the issue number (GH-xxxx)

By submitting this pull request, I acknowledge that I am making a contribution to the Apache Software Foundation under the terms and conditions of the Contributor's Agreement.

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See the Apache Jena "Contributing" guide.

[rvesse]

LGTM, I'll let @afs have chance to review before merging as this is more his area of the codebase