Flaky test: IngestionSmokeTest times out on JDK 25 (multiple unrelated methods)

IngestionSmokeTest hits the 20 s LatchableEmitter timeout intermittently on the JDK 25 CI matrix (test-jdk25-[I*,A*,U*]). Three unrelated methods fail in the same run, all at the exact 20 s wall — a load/timing pattern, not a regression.

```
embedded-tests/target/test-classes/org/apache/druid/testing/embedded/indexing/IngestionSmokeTest.class:282 | Timed out waiting for event after [20,000]ms 20.391s
embedded-tests/target/test-classes/org/apache/druid/testing/embedded/indexing/IngestionSmokeTest.class:337 | Timed out waiting for event after [20,000]ms 20.015s
embedded-tests/target/test-classes/org/apache/druid/testing/embedded/indexing/IngestionSmokeTest.class:166 | Timed out waiting for event after [20,000]ms 20.019s
ℹ️ Posting with conclusion 'failure' to https://github.com/apache/druid/pull/19311 (sha: 2d094d5fbe6e11b6d22b1df8bf54c8cf7b7d03d2)
🚀 Publish results
ℹ️ - Test Report - test-jdk25-[I*,A*,U*] - 18604 tests run, 17847 passed, 754 skipped, 3 failed.
🧪 - embedded-tests/target/test-classes/org/apache/druid/testing/embedded/indexing/IngestionSmokeTest.class | Timed out waiting for event after [20,000]ms
🧪 - embedded-tests/target/test-classes/org/apache/druid/testing/embedded/indexing/IngestionSmokeTest.class | Timed out waiting for event after [20,000]ms
🧪 - embedded-tests/target/test-classes/org/apache/druid/testing/embedded/indexing/IngestionSmokeTest.class | Timed out waiting for event after [20,000]ms

```

Start with embedded-tests/.../IngestionSmokeTest and the LatchableEmitter timeout, then run the test-jdk25-[I*,A*,U*] CI matrix to reproduce the three 20-second failures. Determine the timing or load-related adjustment needed; done means the matrix no longer intermittently times out in these methods.

Written by the indexing model from the issue text.