vulkan: apply atan2 zero workaround to packed shaders

[LEKKO2310]

Summary

Apply the existing packed-vector atan(0, 0) workaround to all non-MoltenVK drivers. Mesa v3dv exhibits the same incorrect vectorized result as llvmpipe, so restricting the workaround to driver ID 13 leaves packed BinaryOp atan2/ratan2 broken on v3dv.

The change covers:

• binaryop_pack4.comp
• binaryop_broadcast_pack4.comp
• binaryop_broadcast_pack1to4.comp

Verification

Built with Vulkan and system glslang on Ubuntu 24.04, then ran test_binaryop_3 with Mesa llvmpipe 25.2.8:

100% tests passed, 0 tests failed out of 1

Fixes #6884.

[tencent-adm]

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1 out of 2 committers have signed the CLA.

✅ LEKKO2310
❌ nihui
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[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 94.88%. Comparing base (5ea9830) to head (c7253b9).
⚠️ Report is 2 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #6930      +/-   ##
==========================================
- Coverage   94.94%   94.88%   -0.06%     
==========================================
  Files        1151     1151              
  Lines      473093   472714     -379     
==========================================
- Hits       449159   448558     -601     
- Misses      23934    24156     +222     

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[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-16T02:31:21.949622Z	c7253b9	New commits

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[nihui]

Thanks for your contribution !