Replacement of peptide at the end of sequence on base (C) rises unnessessury error message

[AlexeyGirin]

Steps to Reproduce

1. Go to Macromolecules mode - Sequence mode
2. Load from file: Replacement of peptide at the end on preset w_out phosphate works wrong.zip
3. Select last monomer (in view mode)
   
4. Go to Library - RNA tab - Bases section
5. Click on C base

Actual behavior
System shows error message: It is impossible to merge fragments. Attachment point to establish bonds are not available.

and replaces A peptide with C base (shown as @ on the sequence mode canvas ) (this is correct)

Expected behavior
No error message appears.
A peptide replaced with C base (shown as @ on the sequence mode canvas )

As per requirement:

4. If the user selects any number of monomers in view mode, and clicks on the monomer card in the library, all selected monomer on the canvas are replaced by chosen monomer from the library each

Versions

• Ketcher Version 2.24.0-rc.1 Build at 2024-08-06; 19:17:47
• Indigo Toolkit Version 1.23.0-rc.1.0-g85f89b8f5-wasm32-wasm-clang-19.0.0
• Windows 10 Pro
• Chrome Version 127.0.6533.100 (Official Build) (64-bit)

Related issue - #4878

[AlexeyGirin]

Fixed.

• Ketcher Version 2.24.0-rc.2 Build at 2024-08-14; 19:00:14
• Indigo Toolkit Version 1.23.0-rc.2.0-g6a2a7526a-wasm32-wasm-clang-19.0.0
• Chrome Version 127.0.6533.100 (Official Build) (64-bit)
• Win10