Refactor renderer and input handling; add OBJ loader and math utilities

- Updated renderer.h to replace Vec3 and Vec2 structs with Math namespace equivalents.
- Introduced Texture struct to manage texture properties.
- Modified Triangle struct to use Texture instead of GLuint for texture handling.
- Removed deprecated matrix functions and replaced them with Math namespace methods.
- Implemented InputManager class for better input handling, including key and mouse state tracking.
- Added ObjLoader class to load OBJ files and associated textures, with MTL file parsing.
- Created math utilities for fixed-point arithmetic and vector/matrix operations.
- Added time management class for frame timing and delta time calculations.

Engine/time/time_manager.cpp

@@ -0,0 +1,32 @@
+#include "time_manager.h"
+#include <GLFW/glfw3.h>
+
+Time::Time()
+    : lastFrameTime(glfwGetTime())
+    , currentFrameTime(lastFrameTime)
+    , deltaTime(0)
+    , elapsedTime(0.0f) {
+}
+
+void Time::Update() {
+    currentFrameTime = glfwGetTime();
+    float deltaTimeSeconds = static_cast<float>(currentFrameTime - lastFrameTime);
+    
+    // Store delta time in fixed-point and update elapsed time
+    deltaTime = SecondsToFixed(deltaTimeSeconds);
+    elapsedTime += deltaTimeSeconds;
+    
+    lastFrameTime = currentFrameTime;
+}
+
+int32_t Time::GetDeltaTime() const {
+    return deltaTime;
+}
+
+float Time::GetElapsedTime() const {
+    return elapsedTime;
+}
+
+int32_t Time::SecondsToFixed(float seconds) const {
+    return static_cast<int32_t>(seconds * FIXED_POINT_SCALE);
+}