[Feature request] Add parsing for extension dependencies

At the moment, in extension's `depends` we can get something like:
```
VK_KHR_get_physical_device_properties2,VK_VERSION_1_1
(VK_KHR_get_memory_requirements2+VK_KHR_get_physical_device_properties2),VK_VERSION_1_1
((VK_KHR_get_physical_device_properties2,VK_VERSION_1_1)+VK_KHR_depth_stencil_resolve),VK_VERSION_1_2
VK_VERSION_1_1
(VK_KHR_spirv_1_4,VK_VERSION_1_2)+VK_KHR_acceleration_structure
VK_KHR_external_semaphore
VK_KHR_get_physical_device_properties2,VK_VERSION_1_1
(VK_KHR_get_physical_device_properties2,VK_VERSION_1_1)+VK_KHR_surface+VK_KHR_get_surface_capabilities2+VK_KHR_swapchain
((VK_KHR_synchronization2+VK_KHR_spirv_1_4+VK_EXT_extended_dynamic_state),VK_VERSION_1_3)+VK_KHR_maintenance5+VK_KHR_pipeline_library
```
It would be really nice if it would be presented in the format easier accessible via Python.
Thanks in advance!

Start by locating the Python code that reads extension `depends` values; the issue provides representative nested expressions to use as input. Define an accessible parsed representation and verify it against those examples, including version requirements and grouped alternatives.

Written by the indexing model from the issue text.