Test read-only and read-write storage texture in in_pass_encoder

[Jiawei-Shao]

This patch adds the tests on read-only and read-write storage textures in in_pass_encoder.spec.ts as the first part to test resource scope rules against all storage texture accesses.

Issue: #3078

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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.)

Requirements for reviewer sign-off:

• Tests are properly located in the test tree.
• Test descriptions allow a reader to "read only the test plans and evaluate coverage completeness", and accurately reflect the test code.
• Tests provide complete coverage (including validation control cases). Missing coverage MUST be covered by TODOs.
• Helpers and types promote readability and maintainability.

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

[jiangzhaoming]

Looks good to me, thanks