Implement PhysicsBridge and ScriptEngine for enhanced physics and scripting capabilities

- Added PhysicsBridge class to manage physics interactions using Bullet Physics.
- Introduced ScriptEngine class to handle Lua scripting, including loading scene objects and managing audio commands.
- Updated test_cube_script to utilize ScriptEngine instead of CubeScript, ensuring compatibility with new architecture.
- Implemented methods for loading meshes, creating physics objects, and handling audio playback within the ScriptEngine.
- Enhanced error handling and input management for Lua scripts.

src/script/physics_bridge.cpp

@@ -0,0 +1,91 @@
+#include "script/physics_bridge.hpp"
+
+#include <btBulletDynamicsCommon.h>
+
+namespace sdl3cpp::script {
+
+PhysicsBridge::PhysicsBridge()
+    : collisionConfig_(std::make_unique<btDefaultCollisionConfiguration>()),
+      dispatcher_(std::make_unique<btCollisionDispatcher>(collisionConfig_.get())),
+      broadphase_(std::make_unique<btDbvtBroadphase>()),
+      solver_(std::make_unique<btSequentialImpulseConstraintSolver>()),
+      world_(std::make_unique<btDiscreteDynamicsWorld>(
+          dispatcher_.get(),
+          broadphase_.get(),
+          solver_.get(),
+          collisionConfig_.get())) {
+    world_->setGravity(btVector3(0.0f, -9.81f, 0.0f));
+}
+
+PhysicsBridge::~PhysicsBridge() {
+    if (world_) {
+        for (auto& [name, entry] : bodies_) {
+            if (entry.body) {
+                world_->removeRigidBody(entry.body.get());
+            }
+        }
+    }
+}
+
+bool PhysicsBridge::addBoxRigidBody(const std::string& name,
+                                    const btVector3& halfExtents,
+                                    float mass,
+                                    const btTransform& transform,
+                                    std::string& error) {
+    if (name.empty()) {
+        error = "Rigid body name must not be empty";
+        return false;
+    }
+    if (!world_) {
+        error = "Physics world is not initialized";
+        return false;
+    }
+    if (bodies_.count(name)) {
+        error = "Rigid body already exists: " + name;
+        return false;
+    }
+    auto shape = std::make_unique<btBoxShape>(halfExtents);
+    btVector3 inertia(0.0f, 0.0f, 0.0f);
+    if (mass > 0.0f) {
+        shape->calculateLocalInertia(mass, inertia);
+    }
+    auto motionState = std::make_unique<btDefaultMotionState>(transform);
+    btRigidBody::btRigidBodyConstructionInfo constructionInfo(
+        mass,
+        motionState.get(),
+        shape.get(),
+        inertia);
+    auto body = std::make_unique<btRigidBody>(constructionInfo);
+    world_->addRigidBody(body.get());
+    bodies_.emplace(name, BodyRecord{
+        std::move(shape),
+        std::move(motionState),
+        std::move(body),
+    });
+    return true;
+}
+
+int PhysicsBridge::stepSimulation(float deltaTime) {
+    if (!world_) {
+        return 0;
+    }
+    return static_cast<int>(world_->stepSimulation(deltaTime, 10, 1.0f / 60.0f));
+}
+
+bool PhysicsBridge::getRigidBodyTransform(const std::string& name,
+                                          btTransform& outTransform,
+                                          std::string& error) const {
+    auto it = bodies_.find(name);
+    if (it == bodies_.end()) {
+        error = "Rigid body not found: " + name;
+        return false;
+    }
+    if (!it->second.motionState) {
+        error = "Rigid body motion state is missing";
+        return false;
+    }
+    it->second.motionState->getWorldTransform(outTransform);
+    return true;
+}
+
+} // namespace sdl3cpp::script