Add option to disable indentation check

We should add [an option](https://github.com/GodotModding/godot-mod-loader/blob/4.x-dev/addons/mod_loader/resources/options_profile.gd) that allows developers to set this when integrating the loader, so detection can be skipped if the option is set.

_Originally posted by @KANAjetzt in https://github.com/GodotModding/godot-mod-loader/issues/587#issuecomment-3865597066_

Start with addons/mod_loader/resources/options_profile.gd and trace where indentation detection reads the integration options. Add the disable option and verify that setting it skips detection while the default behavior remains unchanged.

Written by the indexing model from the issue text.