Fix up to a 1s delay in first produce to new topic

[milindl]

Currently, when creating a new rkt via the public api, rd_kafka_topic_new(), causes us to immediately make a leader query if the topic is unknown.

On the other hand, using the internal rd_kafka_topic_new0() does not do this. producev and produceva both call rd_kafka_topic_new0 in case topic is provided by name. So this delays produce until scan_all is run, which runs on a 1s timer.

Definitely affects JS client and I think it affects python client and dotnet client as well.

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[Copilot]

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tests/0055-producer_latency.c:496

• [nitpick] The variable 'wait_time_mss' appears ambiguous; consider renaming it to 'wait_times_ms' for clarity.

int wait_time_mss[] = {500, 1200, 2500, 3700, 4900};

[Copilot]

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Comments suppressed due to low confidence (1)

tests/0055-producer_latency.c:500

• [nitpick] The variable name 'wait_time_mss' appears to contain a typo; consider renaming it to 'wait_time_ms' for clarity.

int wait_time_mss[] = {500, 1200, 2500, 3700, 4900};