Added width/height tracking to the window class via a GLFW
resize callback. The callback stores the current size and
forwards it to a user-provided std::function.
Added context::set_size() to update the GL viewport when
the window is resized.
Changed scene::render() to accept (int width, int height)
parameters so scenes can compute the correct aspect ratio
for their projection matrix instead of hardcoding 1280/720.
Fixed parameter shadowing in resize_callback_impl
(glfw_window instead of window).
Extract GLFW window management into a dedicated cbt::window
class (new files in cbt/). The opengl::context now only
handles GLAD setup and context activation (no more window
creation or GLFW init/terminate).
Updated main loop in cuber.cpp, CMakeLists.txt (to build
the new source), and AGENTS.md (docs + source layout).
Addresses the design note in context.cpp about mixing
concerns.
- Replace window class with cbt::opengl::context
- Add buffer resource (VBO, EBO, UBO, SSBO) with move semantics
- Add texture resource with format/type enums and filtering
- Add descriptor_set for Vulkan-style resource binding
- All resources use RAII with proper cleanup
portersky