swap HydroForces/HydroSystem naming for semantic clarity

Rename user-facing façade from HydroForces to HydroSystem to align with
Chrono conventions (ChSystem = main entry point). Rename internal
Chrono-free force engine from HydroSystem to HydroForces (in
hydrochrono::hydro namespace) since it computes forces.

Changes:
- HydroForces → HydroSystem (user-facing façade, include/hydroc/hydro_system.h)
- HydroSystem → hydrochrono::hydro::HydroForces (internal engine, include/hydroc/core/hydro_forces.h)
- Add backward-compat aliases: TestHydro, HydroForces → HydroSystem
- Add compatibility header (hydro_forces.h → hydro_system.h) for existing includes
- Update ChronoHydroCoupler, setup_from_yaml, CMakeLists.txt

No behavioral changes; all existing tests pass.

Author: dav-og

CMakeLists.txt

@@ -345,7 +345,7 @@ set(HYDROCHRONO_SOURCES
     src/hydro/config/setup_from_yaml.cpp
     src/hydro/config/yaml_discovery.cpp
     # Core facade and utilities
-    src/hydro/hydro_forces.cpp
+    src/hydro/hydro_system.cpp
     src/hydro/utils/helper.cpp
     # Hydro modules
     src/hydro/waves/wave_base.cpp
@@ -354,7 +354,7 @@ set(HYDROCHRONO_SOURCES
     src/hydro/waves/irregular_wave.cpp
     src/hydro/radiation/radiation_rirf_processing.cpp
     src/hydro/radiation/radiation_rirf_convolution.cpp
-    src/hydro/core/hydro_system.cpp
+    src/hydro/core/hydro_forces.cpp
     # Chrono coupling layer (bridges Chrono physics with Chrono-free core)
     src/hydro/chrono/chrono_state_utils.cpp
     src/hydro/chrono/chrono_hydro_coupler.cpp

include/hydroc/core/hydro_system.h include/hydroc/core/hydro_forces.hinclude/hydroc/core/hydro_system.h renamed to include/hydroc/core/hydro_forces.h

@@ -1,17 +1,17 @@
 /*********************************************************************
- * @file  hydro_system.h
- * @brief HydroSystem: Chrono-free core that orchestrates force components.
+ * @file  hydro_forces.h
+ * @brief HydroForces: Chrono-free core that orchestrates force components.
  *
  * MAIN TYPES:
- *   - HydroSystem: Owns force components, computes total BodyForces
- *   - HydroSystemProfileStats: Timing/call counts per component type
+ *   - HydroForces: Owns force components, computes total BodyForces
+ *   - HydroForcesProfileStats: Timing/call counts per component type
  *
- * ROLE: This is the Chrono-free hydrodynamics core. HydroForces (façade)
- * and ChronoHydroCoupler delegate force computation to HydroSystem.
+ * ROLE: This is the Chrono-free hydrodynamics core. HydroSystem (façade)
+ * and ChronoHydroCoupler delegate force computation to HydroForces.
  *********************************************************************/
 
-#ifndef HYDROC_CORE_HYDRO_SYSTEM_H
-#define HYDROC_CORE_HYDRO_SYSTEM_H
+#ifndef HYDROC_CORE_HYDRO_FORCES_H
+#define HYDROC_CORE_HYDRO_FORCES_H
 
 #include <hydroc/core/system_state.h>
 #include <hydroc/core/force_component.h>
@@ -21,11 +21,11 @@
 namespace hydrochrono::hydro {
 
 /**
- * @brief Profiling statistics for HydroSystem components.
+ * @brief Profiling statistics for HydroForces components.
  * 
  * Tracks cumulative execution time and call counts for each component type.
  */
-struct HydroSystemProfileStats {
+struct HydroForcesProfileStats {
     double hydrostatics_seconds = 0.0;
     double radiation_seconds    = 0.0;
     double excitation_seconds   = 0.0;
@@ -41,21 +41,21 @@ struct HydroSystemProfileStats {
 };
 
 /**
- * @brief HydroSystem: orchestrates force components to compute total forces.
+ * @brief HydroForces: orchestrates force components to compute total forces.
  * 
  * Owns a collection of force components (hydrostatics, radiation, excitation)
  * and evaluates their combined contributions given system state and time.
- * This is a Chrono-free façade for force computation.
+ * This is a Chrono-free engine for force computation.
  */
-class HydroSystem {
+class HydroForces {
 public:
     /**
      * @brief Constructor.
      * 
      * @param num_bodies Number of bodies in the system
      * @param components Vector of force components (ownership transferred via move)
      */
-    HydroSystem(int num_bodies,
+    HydroForces(int num_bodies,
                 std::vector<std::unique_ptr<IHydroForceComponent>> components);
 
     /**
@@ -83,9 +83,9 @@ class HydroSystem {
      * 
      * Returns cumulative timing and call counts for each component type.
      * 
-     * @return HydroSystemProfileStats Profiling statistics
+     * @return HydroForcesProfileStats Profiling statistics
      */
-    HydroSystemProfileStats GetProfileStats() const { return profile_stats_; }
+    HydroForcesProfileStats GetProfileStats() const { return profile_stats_; }
 
     /**
      * @brief Reset profiling statistics.
@@ -113,11 +113,11 @@ class HydroSystem {
 private:
     int num_bodies_;
     std::vector<std::unique_ptr<IHydroForceComponent>> components_;
-    mutable HydroSystemProfileStats profile_stats_;
+    mutable HydroForcesProfileStats profile_stats_;
     bool profiling_enabled_ = false;  ///< Profiling disabled by default
 };
 
 }  // namespace hydrochrono::hydro
 
-#endif  // HYDROC_CORE_HYDRO_SYSTEM_H
+#endif  // HYDROC_CORE_HYDRO_FORCES_H
 

include/hydroc/coupling/chrono_coupler.h

@@ -1,19 +1,19 @@
 /*********************************************************************
  * @file  chrono_coupler.h
- * @brief ChronoHydroCoupler: bridges Chrono bodies and HydroSystem.
+ * @brief ChronoHydroCoupler: bridges Chrono bodies and HydroForces.
  *
  * MAIN TYPES:
- *   - ChronoHydroCoupler: Adapter between Chrono and HydroSystem
+ *   - ChronoHydroCoupler: Adapter between Chrono and HydroForces
  *
- * ROLE: Extracts SystemState from Chrono bodies, invokes HydroSystem
- * to compute forces. Used internally by HydroForces façade.
+ * ROLE: Extracts SystemState from Chrono bodies, invokes HydroForces
+ * to compute forces. Used internally by HydroSystem façade.
  *********************************************************************/
 
 #ifndef HYDROC_COUPLING_CHRONO_COUPLER_H
 #define HYDROC_COUPLING_CHRONO_COUPLER_H
 
 #include <hydroc/core/system_state.h>
-#include <hydroc/core/hydro_system.h>
+#include <hydroc/core/hydro_forces.h>
 #include <chrono/physics/ChBody.h>
 #include <vector>
 #include <memory>
@@ -26,27 +26,27 @@ void BuildSystemStateFromChronoBodies(
     SystemState& out_state);
 
 /**
- * @brief ChronoHydroCoupler: bridges Chrono bodies and HydroSystem.
+ * @brief ChronoHydroCoupler: bridges Chrono bodies and HydroForces.
  * 
- * Extracts state from Chrono bodies, evaluates forces via HydroSystem,
+ * Extracts state from Chrono bodies, evaluates forces via HydroForces,
  * and (in future) applies forces back to Chrono bodies. This is the
- * adapter between Chrono's physics engine and the Chrono-free HydroSystem.
+ * adapter between Chrono's physics engine and the Chrono-free HydroForces.
  */
 class ChronoHydroCoupler {
 public:
     /**
      * @brief Constructor.
      * 
-     * @param hydro_system Shared pointer to HydroSystem for force evaluation
+     * @param hydro_forces Shared pointer to HydroForces for force evaluation
      * @param bodies Vector of Chrono body pointers
      */
-    ChronoHydroCoupler(std::shared_ptr<HydroSystem> hydro_system,
+    ChronoHydroCoupler(std::shared_ptr<HydroForces> hydro_forces,
                        std::vector<std::shared_ptr<chrono::ChBody>> bodies);
 
     /**
      * @brief Evaluate hydrodynamic forces.
      * 
-     * Extracts state from Chrono bodies, calls HydroSystem to compute
+     * Extracts state from Chrono bodies, calls HydroForces to compute
      * forces, and returns the result.
      * 
      * @param time Current simulation time
@@ -64,31 +64,30 @@ class ChronoHydroCoupler {
     void ApplyForcesToChrono(const BodyForces& forces);
 
     /**
-     * @brief Get profiling statistics from HydroSystem.
+     * @brief Get profiling statistics from HydroForces.
      * 
      * Returns cumulative timing and call counts for each component type.
      * 
-     * @return HydroSystemProfileStats Profiling statistics
+     * @return HydroForcesProfileStats Profiling statistics
      */
-    HydroSystemProfileStats GetProfileStats() const { 
-        return hydro_system_->GetProfileStats(); 
+    HydroForcesProfileStats GetProfileStats() const { 
+        return hydro_forces_->GetProfileStats(); 
     }
 
     /**
-     * @brief Enable or disable profiling in HydroSystem.
+     * @brief Enable or disable profiling in HydroForces.
      * 
      * @param enabled True to enable profiling, false to disable
      */
     void SetProfilingEnabled(bool enabled) {
-        hydro_system_->SetProfilingEnabled(enabled);
+        hydro_forces_->SetProfilingEnabled(enabled);
     }
 
 private:
-    std::shared_ptr<HydroSystem> hydro_system_;
+    std::shared_ptr<HydroForces> hydro_forces_;
     std::vector<std::shared_ptr<chrono::ChBody>> bodies_;
 };
 
 }  // namespace hydrochrono::hydro
 
 #endif  // HYDROC_COUPLING_CHRONO_COUPLER_H
-