basalt-26.3: sql/tests: TestSplitAtTableBoundary failed

sql/tests.TestSplitAtTableBoundary [failed](https://mesolite.cluster.engflow.com/invocations/default/9ea0a42c-3357-4a98-87e5-bad2cc10c7bf?testReportRun=1&testReportShard=16&testReportAttempt=1#targets-Ly9wa2cvc3FsL3Rlc3RzOnRlc3RzX3Rlc3Q=) on basalt-26.3 @ [ff08b7555b39cd48a80fffeb988204d855ac8be3](https://github.com/cockroachdb/cockroach/commits/ff08b7555b39cd48a80fffeb988204d855ac8be3):

```
=== RUN TestSplitAtTableBoundary
test_log_scope.go:172: test logs captured to: outputs.zip/logTestSplitAtTableBoundary2027137628
test_log_scope.go:82: use -show-logs to present logs inline
test_server_shim.go:168: automatically injected a shared process virtual cluster under test; see comment at top of test_server_shim.go for details.
table_split_test.go:53: condition failed to evaluate within 3m45s: from table_split_test.go:60: expected range start key /Tenant/10/Table/106; got /Tenant/10/Table/84

goroutine dump: /mnt/engflow/worker/work/1/exec/bazel-out/k8-fastbuild/testlogs/pkg/sql/tests/tests_test/shard_16_of_16_run_1_of_3/test.outputs/goroutine_dump_3982775817.txt
panic.go:694: -- test log scope end --
test logs left over in: outputs.zip/logTestSplitAtTableBoundary2027137628
--- FAIL: TestSplitAtTableBoundary (2063.41s)
```

Parameters:
- attempt=1
- race=true
- run=1
- shard=16
Help

See also: [How To Investigate a Go Test Failure \(internal\)](https://cockroachlabs.atlassian.net/l/c/HgfXfJgM)

Same failure on other branches

- #175509 basalt-26.3.2-rc-20260914: sql/tests: TestSplitAtTableBoundary failed [C-test-failure O-robot T-sql-queries branch-basalt-26.3.2-rc-20260914 release-blocker]
- #175463 sql/tests: TestSplitAtTableBoundary failed [C-test-failure O-robot T-sql-queries branch-master]
- #175422 basalt-26.3.2-rc-20260913: sql/tests: TestSplitAtTableBoundary failed [OOM] [C-test-failure O-robot T-sql-queries branch-basalt-26.3.2-rc-20260913]
- #174997 basalt-26.3.2-rc-20260908: sql/tests: TestSplitAtTableBoundary failed [OOM] [C-test-failure O-robot T-sql-queries branch-basalt-26.3.2-rc-20260908]
- #174915 basalt-26.3.2-rc-20260908: sql/tests: TestSplitAtTableBoundary failed [C-test-failure O-robot T-sql-queries branch-basalt-26.3.2-rc-20260908]
- #174818 release-26.3: sql/tests: TestSplitAtTableBoundary failed [C-test-failure O-robot T-sql-queries branch-release-26.3]
- #174815 release-26.2: sql/tests: TestSplitAtTableBoundary failed [OOM] [C-test-failure O-robot T-sql-queries branch-release-26.2]

[This test on roachdash](https://roachdash.crdb.dev/?filter=status:open%20t:.*TestSplitAtTableBoundary.*&sort=title+created&display=lastcommented+project) | [Improve this report!](https://github.com/cockroachdb/cockroach/tree/master/pkg/cmd/bazci/githubpost/issues)

Jira issue: CRDB-68426

Start with sql/tests/table_split_test.go, especially the failure at line 53 and the expectation at line 60, then inspect the captured test logs and goroutine dump linked in the report. Reproduce TestSplitAtTableBoundary and determine why the expected range start key /Tenant/10/Table/106 is instead /Tenant/10/Table/84; done means the test passes reliably on the affected branches.

Written by the indexing model from the issue text.