feat(ivp): first-class sensitivity analysis API

[Ryan-D-Gast]

🎯 What
Introduces a first-class structured API within the IVP builder for computing parametric sensitivities (both Forward and Adjoint) dynamically and explicitly.

• ParametrizedODE Trait: A new mathematical abstraction providing parameter declarations and the requisite parameter Jacobian (jacobian_p) evaluations.
• System Wrappers: Reusable ForwardSensitivityOde and AdjointOde structs that cleanly wrap an underlying generic ODE, seamlessly generating the augmented derivative computations via dS/dt = J_y * S + J_p (Forward) and backward evaluation via J_y^T, J_p^T transpositions alongside exact internal endpoint cubic Hermite interpolation.
• IVP Enhancements: Brand new first-class ode_forward_sensitivity and ode_adjoint_sensitivity initialization methods right on the IVP builder.

📊 Coverage
Refactored and tested Example 15 (ode_15_forward_sensitivity_analysis) and Example 16 (ode_16_adjoint_sensitivities) to directly leverage the IVP builder integrations over their previous manual ad-hoc setups. Output solutions correctly verify against analytical equations and central finite-differences.

✨ Result
Provides a robust parameter-fitting and sensitivity calculation architecture immediately accessible to any standard numerical method implementation within the project via straightforward builder methodology.

Closes #74

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PR created automatically by Jules for task 7475342233764524364 started by @Ryan-D-Gast

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