Implement relational cohesion metric

[barnabasdomozi]

Closes #680

[Copilot]

Pull Request Overview

This PR implements a relational cohesion metric for C++ modules to enhance code quality analysis and closes issue #680.

• Adds a new test suite for relational cohesion (ParameterizedRelationalCohesionTest) with corresponding sample modules in rc_module_a, rc_module_b, and rc_module_c.
• Implements the relational cohesion metric calculation in the metrics parser and updates the relevant data models and views.
• Updates the parser header and database model files to support the new metric.

Reviewed Changes

Copilot reviewed 15 out of 15 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
plugins/cpp_metrics/test/src/cppmetricsparsertest.cpp	Adds tests to verify relational cohesion metric behavior.
plugins/cpp_metrics/test/sources/parser/rc_module_*	Introduces sample modules to simulate internal type relationships.
plugins/cpp_metrics/parser/src/cppmetricsparser.cpp	Implements relational cohesion metric computation using a new function.
plugins/cpp_metrics/parser/include/cppmetricsparser/cppmetricsparser.h	Declares the new relational cohesion method and its partition multiplier.
plugins/cpp_metrics/model/include/model/cpptypedependencymetrics.h	Adds a new DB view for counting type dependencies for the metric.
plugins/cpp_metrics/model/include/model/cppfilemetrics.h	Updates the file metrics type and value to support double values for the metric.
plugins/cpp_metrics/model/include/model/cppcohesionmetrics.h	Adds a new DB view to support cohesion metric counting.

[mcserep]

CppMetricsServiceHandler::getCppModuleMetricsTypeNames() should be extended with the new module metrics.

[mcserep]

CppMetricsServiceHandler::getCppModuleMetricsTypeNames() should be extended with the new module metrics.

Fixed in f6b46a7.