MINIFICPP-2840 - Refactor provenance part 1

[adamdebreceni]

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[Copilot]

Pull request overview

This PR is the first part of a provenance refactor, focusing on modernizing the provenance/flowfile APIs (naming and types) and simplifying repository record retrieval to return a vector of deserialized components.

Changes:

• Renames getlineageStartDate() to getLineageStartDate() across FlowFile/Provenance APIs and call sites.
• Refactors core::Repository::getElements from an out-parameter/bool API to std::vector<...> getElements(size_t max_size).
• Updates provenance event/reporting plumbing (component id now uses processor UUID; JSON report builder returns a std::string).

Reviewed changes

Copilot reviewed 20 out of 20 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
minifi-api/include/minifi-cpp/provenance/Provenance.h	API rename for lineage start date; removes parent/child “remove” APIs.
minifi-api/include/minifi-cpp/core/Repository.h	Changes getElements API to return a vector.
minifi-api/include/minifi-cpp/core/FlowFile.h	Renames getlineageStartDate to getLineageStartDate in the API.
libminifi/test/libtest/unit/ProvenanceTestHelper.h	Updates test repository to new getElements signature and provenance record creation.
libminifi/src/provenance/Provenance.cpp	Refactors ProvenanceEventRecordImpl fields/ctor usage; updates serialization/deserialization and reporter commit loop.
libminifi/src/core/reporting/SiteToSiteProvenanceReportingTask.cpp	Refactors JSON report generator to return string; adapts to new getElements API.
libminifi/src/core/ProcessSession.cpp	Passes processor UUID as provenance component id; updates lineage start date call.
libminifi/src/core/FlowFile.cpp	Renames FlowFileImpl method to getLineageStartDate.
libminifi/src/core/flow/FlowSchema.cpp	Adds NiFi flow JSON keys for provenance reporting section/fields.
libminifi/include/provenance/Provenance.h	Refactors provenance impl types/ctors and member naming; removes default ctor.
libminifi/include/core/reporting/SiteToSiteProvenanceReportingTask.h	Updates getJsonReport signature (returns string); removes onSchedule override declaration.
libminifi/include/core/FlowFile.h	Renames FlowFileImpl virtual override to getLineageStartDate.
extensions/standard-processors/tests/unit/ProcessorTests.cpp	Updates tests for provenance record creation and new reporting task API.
extensions/standard-processors/processors/LogAttribute.cpp	Updates lineage start date getter name.
extensions/rocksdb-repos/tests/ProvenanceTests.cpp	Updates record loading creation to use ProvenanceEventRecord::create(); removes child UUID removal assertions.
extensions/rocksdb-repos/ProvenanceRepository.h	Updates provenance repository interface to new getElements signature.
extensions/rocksdb-repos/ProvenanceRepository.cpp	Implements new getElements signature returning a vector.
extensions/grafana-loki/PushGrafanaLokiREST.cpp	Updates lineage start date getter name.
extensions/grafana-loki/PushGrafanaLokiGrpc.cpp	Updates lineage start date getter name.
core-framework/include/core/Repository.h	Updates default repository implementation to new getElements signature.

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[fgerlits]

LGTM; added some nitpicks