Test Vulkan Extension

1. Check that we were told which Vulkan extension we are supposed to check. If this was not specified, ask.
2. Check that we were told which test or common code to use as a starting point or if we should make a test from scratch. If this was not specified, ask.
3. Download the extension text from https://docs.vulkan.org/refpages/latest/refpages/source/<extension name>.html and read it.
4. If you cannot download the extension text due to sandbox permission issues, ask user to add the following to their ~/.codex/config.toml:

[network]
enable_domain_allowlist = true
domain_allowlist = [
  "docs.vulkan.org",
  "github.com",
  "api.github.com"
]

5. Check that we have a test for each new Vulkan command and struct defined in the given extension, if possible. If there are features gated by enable flags, make sure we only run these gates features when they are supported. Sometimes creating a new test is the right choice, sometimes we can just insert usage into existing tests.
6. If we can verify some generated output with vkAssertBuffer, that's is good.
7. Try to use test_set_name and test_marker_mention with any new object handles so that we can test this works as well.
8. If the test generates a visual image, consider adding an -i option for user to dump the image to disk for verification.
9. Run make -j 6 in the build directory. Fix any build issues.
10. Run ./<test name> -v --cpu from the build directory and fix any validation issues.
11. Run the test with VK_INSTANCE_LAYERS=VK_LAYER_LUNARG_api_dump environment variable set to verify that the new commands we wanted to test actually got executed.
12. Make note of any commands and structs you could not add to the test, things you find that did not make sense, and suggest the best improvement that could be made to make the test even better.
13. Make sure usage detection of this extension is in src/usagetracker/vulkan_feature_detect.cpp and src/usagetracker/vulkan_feature_detect.h. You can use the skill $vulkan-extension-detection to add this if missing.