MINIFICPP-2852 Implement LMDB based flow file repository

[lordgamez]

https://issues.apache.org/jira/browse/MINIFICPP-2852

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[Copilot]

Pull request overview

Implements an LMDB-backed FlowFile repository and extracts shared LMDB database operations for reuse.

Changes:

• Adds configurable LMDB FlowFile persistence and recovery.
• Introduces a shared LMDB wrapper.
• Updates LMDB content repository and tests.

Reviewed changes

Copilot reviewed 14 out of 14 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
Configuration.h	Adds FlowFile LMDB size property.
Configuration.cpp	Registers property validation.
LmdbStreamTests.cpp	Adapts stream tests to the wrapper.
LmdbFlowFileRepositoryTests.cpp	Tests the new repository.
LmdbContentSessionTests.cpp	Updates repository namespace.
LmdbContentRepositoryTests.cpp	Updates namespace and logging tests.
LmdbWrapper.h	Declares shared LMDB operations.
LmdbWrapper.cpp	Implements shared LMDB operations.
LmdbStream.h	Integrates streams with the wrapper.
LmdbStream.cpp	Delegates stream persistence to the wrapper.
LmdbFlowFileRepository.h	Declares the FlowFile repository.
LmdbFlowFileRepository.cpp	Implements persistence, recovery, and deletion.
LmdbContentRepository.h	Refactors content storage around the wrapper.
LmdbContentRepository.cpp	Delegates content operations to the wrapper.

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