Prevent empty NSQ batches and bound HTTP waits

[arthurianresolve]

Summary

Improve NSQMetricsReporter reliability and make its HTTP timeout configurable through each supported setup path:

• do not post empty metric batches
• set connection-pool, connection, and response-inactivity timeouts
• allow direct Java callers to override the timeout through NSQMetricsReporterFactory.Builder
• bind metrics.reporter.timeout for Spring services
• bind dw.metrics.reporter.timeout.millis for CDI services
• fail clearly when an explicit timeout is used with a reporter that does not support it

Root cause

flush() sent a request even when its buffer was empty. The Apache HTTP client also had no connection-request, connection, or socket timeout, so a slow NSQ endpoint could delay later reporting cycles. Service configuration paths could not pass a timeout to the NSQ builder.

Impact

NSQ no longer receives empty /mpub requests. HTTP waits use a 10-second default limit, and a timed-out request does not prevent a later batch from being attempted. Java, Spring, and CDI deployments can override the shared limit.

Configuration

The default timeout is 10 seconds for the connection-pool wait, connection attempt, and response wait.

• Direct Java: call withTimeout(...) on the NSQ builder.
• Spring: set metrics.reporter.timeout with Spring duration syntax, such as 10s, 500ms, or a bare number of seconds.
• CDI: set dw.metrics.reporter.timeout.millis to a positive millisecond value. The default -1 leaves the reporter's own default unchanged.

When the property is omitted, existing behavior uses the reporter's 10-second default. Setting it for an unsupported reporter fails with a clear configuration error. The original five-argument CDI producer overload remains available for source and binary compatibility.

Release sequencing

The new builder capability is in metrics-reporter:3.0.1-SNAPSHOT, and the root and starter reactors point to that version so this draft can build the producer and consumers together.

Before this PR is ready to merge, publish immutable metrics-reporter:3.0.1 and replace both snapshot version pins with 3.0.1. Clean reactors that do not include the opt-in metrics-reporter module must not depend on the snapshot.

Integration

This PR overlaps #3743 in NSQMetricsReporter. Whichever PR merges second should rebase and retain both #3743's UTF-8 byte sizing/writes and this PR's empty-batch and timeout changes, then rerun the metrics-reporter tests.

Test

Windows host: Java 11.0.31 and Maven 3.9.16.

Passed:

• Full metrics-reporter module: 5 tests, 0 failures, 0 errors, 0 skipped.
• Full spring-boot-starter-datawave module: 43 tests, 0 failures, 0 errors, 0 skipped.
• Full datawave-ws-common module: 68 tests, 0 failures, 0 errors, 0 skipped.
• CDI compatibility reactor: all 22 required modules built successfully; MetricsCdiConfigurationTest passed.

Coverage includes:

• empty direct flushes
• oversized and rollover batches
• all three Apache HTTP timeout values
• a local server that responds after the configured limit
• a later successful batch after a timeout
• Spring binding for omitted, millisecond-suffixed, and bare-second values
• capable, unsupported, omitted, and invalid timeout configuration branches
• CDI millisecond configuration and preservation of the existing producer overload

Fixes #3732
Fixes #3753