MINIFICPP-2603 Add Record Reader and Record Writer properties to MQTT processors

[lordgamez]

https://issues.apache.org/jira/browse/MINIFICPP-2603

Depends on #1997

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[Copilot]

Pull Request Overview

This PR adds Record Reader and Record Writer properties to the MQTT processors (PublishMQTT and ConsumeMQTT) to enable structured record processing. Instead of treating MQTT messages as raw payloads, these processors can now parse messages into records using a Record Reader and serialize them back using a Record Writer.

• Adds Record Reader and Record Writer properties to both PublishMQTT and ConsumeMQTT processors
• Implements record-based processing logic that splits individual records for publishing and aggregates records for consuming
• Includes comprehensive test coverage for the new functionality

Reviewed Changes

Copilot reviewed 22 out of 22 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
minifi-api/include/minifi-cpp/core/Record.h	Adds constructor and contains() method to Record class for better record manipulation
extensions/standard-processors/processors/SplitRecord.cpp	Refactors to use common utility function for getting RecordSetIO services
extensions/mqtt/processors/PublishMQTT.h	Adds Record Reader/Writer properties and makes sendMessage method virtual for testing
extensions/mqtt/processors/PublishMQTT.cpp	Implements record processing logic that splits records into individual flow files
extensions/mqtt/processors/ConsumeMQTT.h	Adds Record Reader/Writer properties and Add Attributes As Fields option
extensions/mqtt/processors/ConsumeMQTT.cpp	Implements record aggregation logic and attribute handling for record mode
extensions/mqtt/processors/AbstractMQTTProcessor.h	Adds record set reader/writer member variables and makes initializeClient virtual
extension-utils/include/utils/ProcessorConfigUtils.h	Adds utility function for getting and validating RecordSetIO services
extensions/mqtt/tests/PublishMQTTTests.cpp	Comprehensive test coverage for record-based publishing functionality
extensions/mqtt/tests/ConsumeMQTTTests.cpp	Comprehensive test coverage for record-based consuming functionality
docker/test/integration/	Integration test setup and scenarios for MQTT record processing
PROCESSORS.md	Documentation updates for new properties and functionality

Comments suppressed due to low confidence (1)

extensions/mqtt/tests/ConsumeMQTTTests.cpp:151

• Spelling error: 'non-existant' should be 'non-existent'.

  REQUIRE_NOTHROW(test_controller_.plan->scheduleProcessor(consume_mqtt_processor_));

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