CNDB-15843 Capture and restore ExecutorLocals in Message.execute and Dispatcher.processInit CC5 Future callbacks that run on a different thread to access expected thread-local state.

[djatnieks]

What is the issue

#15843: Fix access to thread-local data in Dispatcher and Message after migration from CompletableFuture to C* Future

What does this PR fix and why was it fixed

CNDB tests, like BillingTest.testBillingWithIsolatedTenant were failing with timeouts that are pretty generic from the driver:

java.lang.IllegalStateException: Trace 692c7d60-b41d-11f0-9dd7-897b41c7f3b5 still not complete after 10 attempts
	at com.datastax.oss.driver.internal.core.cql.QueryTraceFetcher.lambda$querySession$1(QueryTraceFetcher.java:95)
	at java.base/java.util.concurrent.CompletableFuture.uniWhenComplete(CompletableFuture.java:859)
	at java.base/java.util.concurrent.CompletableFuture$UniWhenComplete.tryFire(CompletableFuture.java:837)
	at java.base/java.util.concurrent.CompletableFuture.postComplete(CompletableFuture.java:506)
	at java.base/java.util.concurrent.CompletableFuture.complete(CompletableFuture.java:2079)
	at com.datastax.oss.driver.internal.core.cql.CqlRequestHandler.setFinalResult(CqlRequestHandler.java:324)
	at com.datastax.oss.driver.internal.core.cql.CqlRequestHandler.access$1500(CqlRequestHandler.java:95)
	at com.datastax.oss.driver.internal.core.cql.CqlRequestHandler$NodeResponseCallback.onResponse(CqlRequestHandler.java:655)
	at com.datastax.oss.driver.internal.core.channel.InFlightHandler.channelRead(InFlightHandler.java:257)

After debugging with ai agent help, it was discovered that the driver was timing out waiting for trace sessions in C* to complete, and the root cause that o.a.c.Future callbacks running on different threads did not have access to the correct ExecutorLocals state.

See the ticket for more details.

[github-actions]

Checklist before you submit for review

• This PR adheres to the Definition of Done
• Make sure there is a PR in the CNDB project updating the Converged Cassandra version
• Use NoSpamLogger for log lines that may appear frequently in the logs
• Verify test results on Butler
• Test coverage for new/modified code is > 80%
• Proper code formatting
• Proper title for each commit staring with the project-issue number, like CNDB-1234
• Each commit has a meaningful description
• Each commit is not very long and contains related changes
• Renames, moves and reformatting are in distinct commits
• All new files should contain the DataStax copyright header instead of the Apache License one

[sonarqubecloud]

Quality Gate failed

Failed conditions
71.4% Coverage on New Code (required ≥ 80%)

See analysis details on SonarQube Cloud

[cassci-bot]

❌ Build ds-cassandra-pr-gate/PR-2093 rejected by Butler

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3 regressions found
See build details here

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Found 3 new test failures

Test	Explanation	Runs	Upstream
o.a.c.cql3.validation.operations.AggregationQueriesTest.testAggregationQueryShouldNotTimeoutWhenItExceedesReadTimeout (compression)	REGRESSION	🔴🔴	2 / 14
o.a.c.distributed.test.NativeProtocolTest.withClientRequests	REGRESSION	🔵🔴	0 / 14
o.a.c.index.sai.disk.v2.sortedterms.SortedTermsTest.testFileValidation (compression)	REGRESSION	🔵🔴	0 / 14

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Found 4 known test failures

[djatnieks]

A comparison of CNDB CI test results from a CNDB branch with these changes compared to the current main-5.0-b1c9b82251 branch results - about 30 fewer test failures.

https://butler-cndb.datastax.com/#/ci/upstream/compare/ci/cndb-15843/to/ci/main-5.0-b1c9b82251

[driftx]

This makes sense since we are async but OSS doesn't need this because it's synchronous.