Performance optimizations and collision improvements

Performance:
- Remove expensive inverse() from all vertex shaders (terrain, WMO, M2, water, character)
- Add uniform location caching to avoid repeated glGetUniformLocation calls
- Add proper frustum culling for WMO groups using AABB intersection
- Add distance-based culling for WMO and M2 instances
- Add cleanup of unused M2/WMO models when tiles unload

Collision & Movement:
- Add M2 doodad collision detection (fences, boxes, etc.)
- Reduce character eye height (5.0 -> 1.8) and collision radius (2.5 -> 0.5)
- Enable WoW-style movement speed by default (14 units/sec run, 5 walk, 9 back)
- Fix emote grammar ("You waves." -> "You wave.")

Misc:
- Rename window title to "Wowee"

include/rendering/shader.hpp

@@ -1,6 +1,7 @@
 #pragma once
 
 #include <string>
+#include <unordered_map>
 #include <GL/glew.h>
 #include <glm/glm.hpp>
 
@@ -25,6 +26,7 @@ public:
     void setUniform(const std::string& name, const glm::vec4& value);
     void setUniform(const std::string& name, const glm::mat3& value);
     void setUniform(const std::string& name, const glm::mat4& value);
+    void setUniformMatrixArray(const std::string& name, const glm::mat4* matrices, int count);
 
     GLuint getProgram() const { return program; }
 
@@ -35,6 +37,9 @@ private:
     GLuint program = 0;
     GLuint vertexShader = 0;
     GLuint fragmentShader = 0;
+
+    // Cache uniform locations to avoid expensive glGetUniformLocation calls
+    mutable std::unordered_map<std::string, GLint> uniformLocationCache;
 };
 
 } // namespace rendering