Add tests for override-sized array pointer parameters

[alan-baker]

Fixes #4629

• Validation and execution tests

Issue: #

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Requirements for PR author:

• All missing test coverage is tracked with "TODO" or .unimplemented().
• New helpers are /** documented */ and new helper files are found in helper_index.txt.
• Test behaves as expected in a WebGPU implementation. (If not passing, explain above.)
• Test have be tested with compatibility mode validation enabled and behave as expected. (If not passing, explain above.)

Requirements for reviewer sign-off:

• Tests are properly located.
• Test descriptions are accurate and complete.
• Tests provide complete coverage (including validation control cases). Missing coverage MUST be covered by TODOs.
• Tests avoid over-parameterization (see case count report).

When landing this PR, be sure to make any necessary issue status updates.

[github-actions]

Results for build job (at 460ae20):

-webgpu:shader,execution,expression,call,user,ptr_params:read_full_object:* - 45 cases, 45 subcases (~1/case)
+webgpu:shader,execution,expression,call,user,ptr_params:read_full_object:* - 54 cases, 54 subcases (~1/case)
-webgpu:shader,execution,expression,call,user,ptr_params:write_full_object:* - 36 cases, 36 subcases (~1/case)
+webgpu:shader,execution,expression,call,user,ptr_params:write_full_object:* - 45 cases, 45 subcases (~1/case)
-webgpu:shader,validation,functions,restrictions:function_parameter_types:* - 57 cases, 57 subcases (~1/case)
-webgpu:shader,validation,functions,restrictions:function_parameter_matching:* - 44 cases, 5544 subcases (~126/case)
+webgpu:shader,validation,functions,restrictions:function_parameter_types:* - 60 cases, 60 subcases (~1/case)
+webgpu:shader,validation,functions,restrictions:function_parameter_matching:* - 47 cases, 6063 subcases (~129/case)
-TOTAL: 281178 cases, 2322743 subcases
+TOTAL: 281202 cases, 2323283 subcases