[Type] Introduce clamped scalar ensuring value not outside bounds

[alxbilger]

This pull request introduces a new foundational type, sofa::type::ClampedScalar. This class template wraps a standard scalar value and guarantees that the stored value cannot fall outside predefined minimum and maximum bounds (min/max).

Key Changes & Implementation Details

1. New Type (ClampedScalar):

   • A templated class that encapsulates a scalar value and two immutable bounds ($\text{minBound}, \text{maxBound}$).
   • The class implements clamping logic in several key areas:
     • Construction: Initial values are automatically clamped upon object creation.
     • Assignment/Setting (operator=): Any attempt to set the value uses clamping, ensuring state integrity.
     • Input/Output Operators: Stream extraction (>>) reads a raw value and clamps it before updating the internal state. Stream insertion (<<) only outputs the valid, clamped value.
     • Prediction: A calculateClamped(T rawValue) method allows users to predict what the bound-constrained result would be without modifying the object's actual state.

2. Integration into VisualMesh Component:

   • The d_elementSpace data member in sofa::component::visual::VisualMesh has been updated from Data<SReal> to Data<type::ClampedScalar<SReal>>.
   • This change ensures that the element space parameter (which must logically be between 0 and 1) is enforced and clamped correctly, making the mesh visualization component more robust.

3. Framework Updates:

   • Added ClampedScalar.h, ClampedScalar.cpp, and corresponding test files (ClampedScalar_test.cpp) to Sofa/framework/Type.
   • Updated CMake files across the framework to correctly include and build this new type.

⚠️ Breaking because of the change of type in VisualMesh.

Companion PR for the GUI: sofa-framework/SofaGLFW#292

clamped.mp4

Local gemma-4-e4b used for documentation and unit tests.

[with-all-tests]

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Reviewers will merge this pull-request only if

• it builds with SUCCESS for all platforms on the CI.
• it does not generate new warnings.
• it does not generate new unit test failures.
• it does not generate new scene test failures.
• it does not break API compatibility.
• it is more than 1 week old (or has fast-merge label).

[fredroy]

Should a ClampedIntegral be implemented also ?