Avoid AIOOBE in and cap getMaxOverlapsPerShard at 64k

[driftx]

Fixes #12991

[cassci-bot]

❌ Build ds-cassandra-pr-gate/PR-1579 rejected by Butler

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42 new test failure(s) in 1 builds
See build details here

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Found 42 new test failures

Showing only first 15 new test failures

Test	Explanation	Branch history	Upstream history
t.TestCqlshUnicode.test_unicode_desc	regression	🔴
o.a.c.d.c.CompactionControllerTest.testMemtable...	regression	🔴
...tCorruptedSSTablesWithLeveledCompactionStrategy	regression	🔴
...thRestartTest.testReadingValuesOfDroppedColumns	regression	🔴
...ersionTest.v4ConnectionCleansUpThreadLocalState	regression	🔴
...d.t.QueriesTableTest.shouldExposeReadsAndWrites	regression	🔴
..., expectedHeaders=[Ljava.lang.String;@6821ea29]	regression	🔴
...eadSizeWarningTest.warnThresholdSinglePartition	regression	🔴
...InvalidQueryTest.testVectorEqualityIsNotAllowed	regression	🔴
o.a.c.i.DiskSpaceMetricsTest.baseline	regression	🔴
o.a.c.i.c.CompressionMetadataTest.testMemoryIsF...	regression	🔴
...ntIrWithPreviewFuzzTest.concurrentIrWithPreview	regression	🔴
o.a.c.r.FailedAckTest.failedAck	regression	🔴
...iteTest.testSingleRowMutationWithSecondaryIndex	regression	🔴
...eTest.testMultipleRowsMutationWithClusteringKey	regression	🔴

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No known test failures found