Second sense chain represented as side chain

[AlexeyGirin]

Steps to Reproduce

1. Go to Macro - Sequence mode (clean canvas)
2. Load from HELM: RNA1{R(A)P.R(A)}|RNA2{R(A)}|PEPTIDE1{U.U.U}|RNA3{R(U)}$PEPTIDE1,RNA3,3:R2-1:R1|RNA3,RNA2,2:pair-2:pair|PEPTIDE1,RNA1,1:pair-2:pair|RNA1,PEPTIDE1,5:pair-2:pair$$$V2.0

Actual behavior
Second sense chain represented as side chain

Expected behavior
Second sense chain represented as sense chain

Versions

• Ketcher Version 3.1.0-rc.2 Build at 2025-02-07; 15:09:23
• Indigo Version 1.29.0-rc.1.0-g2e30df8f7-wasm32-wasm-clang-19.0.0
• Chrome Version 133.0.6943.54 (Official Build) (64-bit)
• Win10

Issue found while testing: #5942