System ignores Display charge option on export to SVG/PNG

KETCHER PART HERE: https://github.com/epam/ketcher/issues/10854

**Steps to Reproduce**
1. Open Remote Ketcher - Molecules mode
2. Load from SMILES: `[OH3+]`

3. Open Settings -> Atoms Section, set `Display charge` to `Off` and press `Apply` button

4. Press `Save as...` button and select `SVG Document` file format

**Actual behavior**
Molecule on the preview has charge visible

It seems that Indigo doesn't have `Display charge` settings option as input parameter

**Expected behavior**
Molecule on the preview doesn't have charge visible

**Versions**
- Ketcher Version 3.19.0-rc.1 Build at 2026-08-03; 17:10:30
- Indigo Version 1.46.0-rc.1.0-gf3408986b-x86_64-linux-gnu-11.2.1
- Chrome Version 151.0.7922.72 (Official Build) (64-bit)
- Win11

Start by tracing the SVG and PNG export path and how the Atoms setting is passed into Indigo during export. Reproduce the `[OH3+]` case with Display charge disabled, then verify that the exported preview omits the charge while normal display behavior remains unchanged.

Written by the indexing model from the issue text.