Extend DotGeneral CSE to recognize operand-swapped equivalence

[Copilot]

Plan: Expand DotGeneral CSE Pass to handle more equivalence

• Understand the current CSE implementation for DotGeneralOp
• Analyze when dot_general(A, B) is equivalent to dot_general(B, A)
• Create a specialized CSE pattern for DotGeneralOp that checks operand swapping
• Add test cases for the new CSE functionality
• Address all code review feedback and eliminate all duplication
• Refactor to reuse more of the generic CSE pattern structure
• Run security checks
• Complete implementation

Original prompt

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This section details on the original issue you should resolve

<issue_title>Expand DotGeneral CSE Pass to handle more equivalence</issue_title>
<issue_description>```
%6 = stablehlo.dot_general %4, %5, batching_dims = [0] x [0], contracting_dims = [1] x [1] : (tensor<4x4xf32>, tensor<4x4xf32>) -> tensor<4xf32>
%7 = stablehlo.dot_general %5, %4, batching_dims = [0] x [0], contracting_dims = [1] x [1] : (tensor<4x4xf32>, tensor<4x4xf32>) -> tensor<4xf32>

This would be an example. `dot_general(A, B)` can be written as `dot_general(B, A)` if certain patterns on the dot_dimensions hold up. we should expand the current dot general cse pass to account for these</issue_description>

## Comments on the Issue (you are @copilot in this section)

<comments>
</comments>

• Fixes Expand DotGeneral CSE Pass to handle more equivalence #1725

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[avik-pal]

@copilot can we reuse more of the CSE struct

[Copilot]

Refactored to follow the structure of the generic CSE pattern more closely. The implementation now directly mirrors the CSE template's iteration and checking logic, only adding the DotGeneral-specific swapped equivalence check. Commit: 9dea61e