[MAINTENANCE] Convert RealSim Core to Simulink Library Block

[yunlishao]

Task Summary
Convert RealSim core components from embedded copies in template models to a centralized Simulink library.

Why is this needed?

• Bug fixes require manual propagation to all test scenarios
• Embedded copies lead to inconsistent behavior across models
• Reduces technical debt and maintenance burden

Scope of Work

• CommonLib/RealSimTemplate.slx
• CommonLib/RealSimTemplate_dSPACE.slx
• Test scenario models

Environment (if version-specific)

• MATLAB/Simulink/dSPACE version: 2024a

Risks or Dependencies

• Existing user models may need updates

Additional Context (optional)
Originated from issue #85 discussion.

[yunlishao]

Implementation Plan

Approach

1. Centralized Simulink Library - All current RealSim blocks and MATLAB Systems will be consolidated into a central Simulink library

2. Legacy Block Support - Existing embedded blocks will be kept until v0.8.0 to maintain backward compatibility

3. Variant Subsystems - Will use Simulink variants to control whether the library targets dSPACE or regular Simulink, eliminating the need for separate template files

Goal

Create a single, centralized location to manage Simulink/dSPACE integration, replacing the current fragmented approach of 5+ different scripts/blocks and embedded MATLAB functions.

This will significantly reduce maintenance overhead and ensure consistent behavior across all models.