It is possible to expand ambiguous monomers on micromolecules canvas

[AlexeyGirin]

Steps to Reproduce

1. Go to Molecules
2. Load from file any ambiguous monomer using Open as New Project: 1. Peptide X (ambiguouse, alternatives, from library).zip
   
3. Right click on appeared monomer and click on Expand monomer at context menu
   

Actual behavior
Some molecule appears on the canvas

Expected behavior
Expand monomer at context menu is disabled for ambiguous monomer

Expanding ambiguous monomer shouldn't be possible to expand

Versions

• Ketcher Version 2.26.0-rc.3 Build at 2024-10-16; 14:35:25
• Indigo Toolkit Version 1.25.0-rc.2.0-g867ae250b-wasm32-wasm-clang-19.0.0
• Chrome Version 129.0.6668.101 (Official Build) (64-bit)
• Win10

Issue found while testing: #5400