Fix converging edges swapping positions when selected

[lmac-1]

Description

This PR fixes a bug where converging edges would swap positions when selected on the diagram.

The issue was caused by sortOrderForSvg reordering edges based on selection state, which affected Dagre's layout decisions. The fix preserves stable edge order regardless of selection.

Before:

After:

See the bug in action: https://www.loom.com/share/302055f6f3b748f1a4523ef7ccef67af

Closes #4328

Validation steps

1. Open workflow with multiple branching points
2. Make sure your diagram is on auto layout mode
3. Click edges from different parent nodes
4. Click edges that lead to converging paths
5. Expected: All paths maintain their positions

Additional notes for the reviewer

1. If you have bigger workflows - perhaps click around on the paths and make sure that everything behaves as expected
2. I suspected that this sorting algorithm was to ensure that the edges stayed on top in terms of z-index. I've verified both with and without the fix that the behaviour remains the same when there are edges that are on top of each other.

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 89.32%. Comparing base (549de66) to head (9a6a604).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4348      +/-   ##
==========================================
+ Coverage   89.29%   89.32%   +0.02%     
==========================================
  Files         425      425              
  Lines       19994    19994              
==========================================
+ Hits        17854    17859       +5     
+ Misses       2140     2135       -5     

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