Indigo/convert error appears in console after selection of SDF and InChl formats on save of arrow in Remote mode

**Steps to Reproduce**

1. Add arrow to Canvas
2. Click on Save as...
3. Select any format (SDF V2000, SDF V3000, InChl, InChl AuxInfo, InChlKey)

**Expected behavior**
- No errors in the console in Remote mode
- TBD - do we need to update the text of error message?

**Actual behavior**
- Error "Convert error! IndigoException: core: is not a molecule" is displayed and indigo/convert error appears in the console:

**Environment details:**
- Indigo Version: 1.23.0-rc.1.0-g85f89b8f5-wasm32-wasm-clang-19.0.0
- Ketcher Version: 2.24.0-rc.1 Build at 2024-08-06; 19:17:47
- OS: Windows 11 Enterprise
- Chrome Version: 127.0.6533.100 (Official Build) (64-bit)

**Additional context**
- Detected during testing for Image feature - https://github.com/epam/Indigo/issues/2029. But the issue isn't related to this feature.